Roadcut Revelations: Unearthing California’s Deep History Along the Highway

Roadcut in Southern California on Angeles Crest Highway (Photo: Erik Olsen)

“Man is a geologic agent,” the late California geologist Eldridge Moores.

Roadcuts in California, those slices through hills and mountainsides made during the construction of roads, are like open books to geologists. They reveal the intricate and often dramatic geological history of the state. When you drive along the highways of California, you’re likely to pass by these exposed cliffs of rock. To the everyday traveler, they might just be a part of the landscape, but to geologists, they are invaluable windows into the Earth’s past.

““Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave,” wrote the great geology (and many other topics) writer John McPhee in his excellent book Annals of the Former World. “To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrane.”

Glacier carved domes tell the story of thousands of years of glaciation in California. (Photo: Erik Olsen)

Roadcuts expose layers of rock that have been hidden from view for millions of years. Each layer, or stratum, tells a story of what the environment was like when that layer was deposited. By studying these layers, geologists can reconstruct a timeline of events that shaped the region. For example, they can identify periods of volcanic activity, times when the area was submerged under an ancient ocean, or epochs when massive glaciers were carving out the valleys.

California is especially interesting due to its active tectonic setting. It’s not just the San Andreas Fault that captivates geologists; there are numerous lesser-known faults that crisscross the state, and roadcuts can expose these hidden fractures. By studying the composition of rocks along these faults, geologists learn about the nature of past seismic activity and can make predictions about future earthquakes.

The rock composition in California varies widely, offering a rich tapestry of geological history. In the Sierra Nevada, granite roadcuts tell of a time when massive chambers of magma slowly cooled and crystallized deep beneath the Earth’s surface. Elsewhere, roadcuts through sedimentary rocks like sandstone and shale may contain fossils, giving clues about the life forms that once inhabited the region.

The San Gabriel Mountains consist of granite rocks of several kinds and a variety of other crystalline rocks, mainly schists, some of which were originally shales and sandstones but have been altered (metamorphosed) by great igneous intrusions and compression. (Photo: Erik Olsen)

These man-made artifacts also reveal the forces that have shaped California’s diverse landscapes. In roadcuts, geologists might find evidence of powerful geological processes such as metamorphism, where existing rock types are transformed into new types due to high pressure and temperature conditions. For instance, the presence of metamorphic rocks like schist and gneiss can indicate ancient collision zones where Earth’s tectonic plates have crashed together.

The value of California roadcuts is wonderfully illustrated in John McPhee’s “Assembling California.” The book is an excellent narrative that weaves the tale of California’s complex geology with the lives of the geologists who study it. Eldridge Moores, a late prominent geologist from the University of California, Davis (Moores died in 2018), played a significant role in deciphering the geological history of the region, particularly through his fieldwork involving roadcuts.

Roadcut in San Gabriel mountains. (Photo: Erik Olsen)

At the time Eldridge Moores entered the field, the theory of plate tectonics was only beginning to gain traction. In the early 1960s, the idea that continents drifted and that vast slabs of the Earth’s crust moved over the mantle was still controversial, met with skepticism by many geologists trained in older, fixist models. Moores, however, embraced the theory early, recognizing in it an explanation for the chaotic structures he saw in California’s mountain belts. As a young researcher, he studied the Troodos ophiolite in Cyprus, an exposed section of ancient oceanic crust, and realized that similar rock assemblages—serpentinized peridotites, deep-sea sediments, and basaltic lavas—were scattered across California.

“It was a very exciting time. I still get goosebumps even talking about it,” Moores told KQED in 2017. “A turning point, I think it was, in the plate tectonic revolution, that was the watershed of geology.”

With plate tectonics as a guiding framework, Moores understood that these rocks were remnants of vanished oceans, relics of seafloor that had been uplifted and accreted onto the edge of North America. His work helped reveal that much of California had arrived in pieces, a geological patchwork of island arcs, deep-sea basins, and continental fragments welded together by subduction. While others were still debating the validity of plate tectonics, Moores was already applying it, using it to decode the assembly of an entire state.

Eldridge Moores at the Cordelia fault.  (Photo: UC Davis)

Moores was renowned for his work on ophiolites, sections of the ocean floor that have been thrust up onto the continent. One of his notable discoveries was the identification of ophiolite sequences in the roadcuts along the highways of the Sierra Nevada. These discoveries were crucial in understanding the ancient tectonic movements that shaped western North America.

Through roadcuts, Moores and his colleagues were able to observe and study the juxtaposition of different rock types, providing further evidence for the theory of plate tectonics. They could literally walk along the cuts and see how different terranes—large packets of rock with a distinct geological history—were stitched together like a geological quilt, offering insight into the past locations of tectonic plates.

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“Nature is messy,” Moores once told McPhee. “Don’t expect it to be uniform and consistent.”

There are thousands of roadcuts across California, each exposing a fragment of the state’s chaotic geology. The Palmdale Roadcut, a striking geological feature along the San Andreas Fault, has been an invaluable resource for geologists studying the dynamics of this infamous fault line. This natural cut exposes a cross-section of the earth, revealing layers of rock and sediment that have been shifted and shaped by seismic activity over millions of years. The rock here is a chaotic mélange—fault gouge, shattered granite, and twisted layers of sedimentary rock that have been pulverized and ground together by the relentless motion of the Pacific and North American plates. By analyzing these layers, geologists can better understand the history and behavior of the San Andreas Fault, including the patterns of past earthquakes and the movements of tectonic plates. This, in turn, contributes significantly to the broader understanding of seismic risks and aids in preparing for future seismic events.

The Palmdale Road Cut on Hwy 14 in Southern California is a 90-foot slice through swirling sediments that have spent millions of years being squeezed and twisted by the San Andreas fault. Some say that this view of the fault is one of the best in all of California.
(Photo: Erik Olsen)

Another geologist, Garniss Curtis, used California roadcuts to study volcanic rocks and their embedded minerals, which allowed for the dating of geologic events with greater precision. His work on the potassium-argon dating method turned roadcuts into time machines, where the age of rocks could be determined with the help of exposed minerals.

One of California’s most well-known roadcuts, the Charlie Brown Outcrop (map), is a favorite among geologists. Located along Highway 178 near the Nevada border, it has been highlighted by geology teacher Garry Hayes, author of the acclaimed Geotripper blog. Hayes says of the roadcut (also known as the Shoshone Roadcut):

“There are really three stories told in this exposure, that of distant ash eruptions, a violent eruption close by, and earthquakes with associated mountain-building.”

Charlie Brown outcrop along highway 178 in California. (Google Maps)

These geologists, among others, have used roadcuts as a means to peel back the layers of time, revealing the processes that have operated to create the state’s diverse geologic scenery. Roadcuts have provided the evidence for groundbreaking theories and have been instrumental in mapping the geological evolution of California. The work of these scientists exemplifies the roadcut’s role as a natural laboratory, a place where Earth’s geologic history is on full display for those who know how to read the rocks.

Moreover, roadcuts are crucial for educating the next generation of geologists. They serve as natural laboratories where students can practice identifying rock types, deciphering the sequence of geological events, and understanding the dynamic forces that continue to shape the Earth.

Roadcuts in California, those slices through hills and mountainsides made during the construction of roads, are like open books to geologists. They reveal the intricate and often dramatic geological history of the state. (Photo: Erik Olsen)

In Assembling California, McPhee remarked that “geologists are like dermatologists: they study, for the most part, the outermost two per cent of the earth. They crawl around like fleas on the world’s tough hide, exploring every wrinkle and crease, and try to figure out what makes the animal move.”

Manmade creations like roadcuts greatly assist geologists in their work. In essence, roadcuts are not just incidental byproducts of infrastructure development; they are key to understanding California’s complex geological evolution. They tell stories of ancient environments, tectonic upheavals, and the slow but inexorable forces that continue to mold the landscape. For geologists in California, the roadcut is a portal into the deep past, offering a tangible connection to the processes that have made the state what it is today.

The Majestic San Gabriel Mountains: A Deep Dive into Their Formation, History, and Biodiversity

Photo: “LA Skyline Mountains2” by Nserrano is licensed under  CC BY-SA 3.0

Towering over Los Angeles like quiet guardians, the San Gabriel Mountains stretch across the northern edge of the city, keeping watch over the busy sprawl below. More than just a dramatic barrier, these mountains are packed with stories of shifting earth, ancient rock, wild weather, and the people who’ve passed through them for thousands of years. They are also a primary source of Southern California beaches. They’re not just a backdrop; they’re a vital part of the region’s identity, full of science, history, and amazing nature.

Part of the Transverse Ranges, a rare east-west trending group of mountains in California, the San Gabriels rise abruptly from the San Gabriel Valley and form a kind of barrier between L.A. and the Mojave Desert. Framed by Interstate 5 to the west and Interstate 15 to the east, the range is anchored on its north side by the famous San Andreas Fault, where the Pacific and North American tectonic plates constantly grind against each other. That ongoing crush is what helped push these peaks up so quickly. Geologically speaking, they’re growing surprisingly quickly.

Side note: The Transverse Ranges also include the Santa Monica Mountains, San Bernardino Mountains, Santa Ynez Mountains, Topatopa Mountains, Tehachapi Mountains, Santa Susana Mountains, and Sierra Madre Mountains.

Inside the range you’ll find the Angeles and San Bernardino National Forests, along with the San Gabriel Mountains National Monument, first established in 2014 and significantly expanded in 2024 to protect more than 450,000 acres of rugged, biodiverse, and culturally significant terrain. (There is excellent hiking in these mountains.) These protected areas include steep canyons, chaparral, rare wildlife, and sites that are important to the history and traditions of Native American communities.

A pool of water from the Arroyo Seco in the San Gabriel Mountain (Erik Olsen)

The rocks here are some of the oldest in the region, but the mountains also tell stories from more recent times: gold miners, early astronomers, hikers, and wildfire researchers. The San Gabriels help shape the weather, store precious snowpack, and remind everyone in L.A. that nature is always nearby and always in motion.

The San Gabriel Mountains offer an impressive rise in elevation, they really kind of explode out of the earth. While the foothills begin at nearly sea level, the highest point in the range is Mount San Antonio, but most people know it as Mount Baldy because, let’s face it, with its distinctive, treeless summit, it looks kind of bald. This peak reaches an altitude of 10,064 feet (3,068 meters). The quick transition from the bustling city to towering peaks is part of the magic of these mountains, a dramatic wall standing guard over downtown Los Angeles.

While the San Gabriels are much smaller in terms of length than, say the Appalachians, they are significantly taller on average. The highest peak in the Appalachians, Mount Mitchell in North Carolina, reaches 6,684 feet (2,037 meters). That’s considerably lower than Mount Baldy in the San Gabriels. The San Gabriels, therefore, boast higher peaks even though they cover a smaller area. However, compared to the Appalachians, which are thought to be billions of years old, the San Gabriel Mountains are relatively young, geologically speaking, and are characterized by rugged and steep features. In essence, being younger, they’ve undergone less erosion.

San Gabriel mountains from La Cañada Flintridge (Photo: Erik Olsen)

It is believed that much of the sand on California’s legendary beaches originated in the San Gabriel mountains, the result of erosion and various rivers and streams that run into the Pacific Ocean.

To understand the story of the San Gabriel Mountains, we need to embark on a temporal journey spanning millions of years. The mountains’ tale starts about 100 million years ago, during the Mesozoic Era, when massive tectonic plates—the Pacific and North American plates—began to converge. The interaction of these tectonic plates was dramatic, with the Pacific Plate subducting, or diving beneath, the North American Plate. This subduction caused the rocks to melt and, over time, rise to form granitic masses known as plutons.

Rocks of a roadcut in the San Gabriel Mountains (Erik Olsen)

As the ages rolled on, these plutons were uplifted, and the erosion of the surrounding softer rocks exposed the granitic cores, giving birth to the San Gabriel Mountains we see today. The primary rock composition of these mountains is granite, with large-grained crystals of feldspar, quartz, and mica that glitter when the sun kisses their surfaces. These mountains also feature significant deposits of sedimentary rocks, particularly in the lower elevations, which date back to the Mesozoic and Cenozoic eras.

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The drainage system of the San Gabriel Mountains is defined by numerous canyons, streams, and arroyos that channel water down from the high elevations into the valleys below. The Arroyo Seco, one of the most well-known waterways, begins near Mount Wilson and flows southwest through Pasadena before merging with the Los Angeles River. Other important streams include the Big Tujunga Creek, which cuts through the mountains to feed into the San Fernando Valley, and the San Gabriel River, which drains much of the range’s eastern side. These waterways are seasonal, swelling during winter rains and spring snowmelt, and often run dry during summer months. Their canyons have been carved by the relentless forces of erosion, creating deep ravines that are vital for wildlife and plant habitats.

Heavy rains cause flooding in the Arroyo Seco near Pasadena. (Erik Olsen)

The San Gabriel Mountains play a critical role in the watershed that serves the greater Los Angeles area. Rain and snowmelt from the mountains replenish groundwater basins and feed into reservoirs, such as the San Gabriel Reservoir and the Morris Reservoir, which are essential for water supply. These mountains act as a natural guidance system, capturing precipitation and funneling it into the region’s aquifers and rivers, supporting both the municipal water supply and flood control efforts. The watershed is crucial for Los Angeles, which depends on these local sources of water to supplement imported supplies from distant regions like the Colorado River and the Owens Valley. The mountain runoff helps maintain the flow of the Los Angeles River, contributing to the city’s efforts to recharge groundwater and ensure a reliable water supply in this semi-arid region.

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When it rains it pours, and sometimes causes landslides

Flood control has long been a central concern in managing the water systems of the San Gabriel Mountains, particularly due to the area’s vulnerability to intense, episodic storms. The steep slopes of the mountains funnel rainwater rapidly into urban areas, leading to a heightened risk of flash floods and debris flows. Over time, this led to the construction of a vast network of catchment basins, dams, and debris basins at the foot of the mountains. These basins are designed to capture stormwater runoff, preventing the overflow of water into densely populated areas and managing the sediment and debris that comes with mountain runoff, which can clog waterways and exacerbate flooding.

Catchment basins in the San Gabriel Mountains are critical for controlling debris flows that occur during and after heavy rains, which can be particularly dangerous in areas where wildfires have stripped the landscape of vegetation. When intense rainstorms hit the steep, fire-scarred slopes, they trigger massive torrents of mud, boulders, and tree debris that rush down the mountain canyons toward the urban foothills. These debris flows can overwhelm creeks and spill into residential neighborhoods, causing widespread destruction. The catchment basins are designed to trap this debris before it reaches populated areas, but their effectiveness depends on regular maintenance and clearing. When these basins fill up too quickly or are not properly maintained, debris can overtop them, leading to significant flooding and property damage.

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A stark example of the dangers posed by debris flows occurred in Montrose in 1934. Following a series of intense storms in the aftermath of the New Year’s Day floods, massive debris flows roared out of the San Gabriel Mountains, devastating the communities of Montrose, La Crescenta, and Tujunga. The floods and debris flows buried homes and roads under several feet of mud and debris, killing at least 45 people. The Montrose landslide became a tragic reminder of the risks associated with living near the San Gabriel Mountains, particularly in the face of severe weather. This event spurred greater investments in flood control infrastructure, including the construction of more robust debris basins to mitigate the effects of future storms.

A fascinating article on the efforts to control debris flows from the San Gabriels, though a bit dated, was penned by John McPhee—whose work we greatly admire. It remains a deeply engaging read on the subject.

The San Gabriel Mountains aren’t just a spectacle of natural processes; they’ve also been a silent witness to numerous significant historical events. The grave of Owen Brown can be found in the mountains just outside of La Canada Flintridge. Owen was the third son of abolitionist John Brown, and has a resting place that has stirred intrigue and speculation for generations. Owen’s grave has become a kind of pilgrimage site for those interested in American history.

Locals gather to celebrate the installation of a gravestone honoring abolitionist Owen Brown on January 29, 1898,
nearly a decade after his death. Photo: Brown family and Paul Ayers.

Owen Brown was a fervent abolitionist like his father and participated in the famous raid on Harpers Ferry. After the tumultuous events that marked his early life, he moved to California, seeking solace in the west. He settled near El Prieto Canyon and lived a relatively secluded life. After his death in 1889, he was buried on a hillside overlooking the canyon, and his grave was marked with a simple headstone. Over time, nature, vandals, and other factors led to the original headstone’s disappearance, adding a layer of mystique to the grave’s location. However, in 2019, a replica of the gravestone was installed.

Mount Wilson telescope

Mount Wilson is another historical wonder in the range. Standing at a towering height of 5,710 feet, it’s not just its elevation that sets Mt. Wilson apart. In the early 20th century, the Mount Wilson Observatory was established, and it soon became a hub of astronomical discoveries. It was here that Edwin Hubble, using the Hooker Telescope, provided evidence of the expansion of the universe—a groundbreaking observation that eventually led to the Big Bang Theory.

Infrastructure Marvel: The Angeles Crest Highway
The human connection to the San Gabriel Mountains was further cemented with the construction of the Angeles Crest Highway in the 1930s. Spanning approximately 66 miles, this scenic byway was a colossal engineering challenge. Its creation provided access to previously remote regions and breathtaking panoramic views that today lure thousands of tourists and nature enthusiasts. The highway is also one of the highest in Southern California, with a summit of 7,903 feet at the Dawson Saddle.

Angeles Crest Highway roadcut (Photo: Erik Olsen)

Driving on the Angeles Crest Highway is an experience that’s both thrilling and a bit nerve-wracking. Winding and twisting through the mountains, you can come across steep drop-offs, sharp turns, and narrow lanes. With elevation changes ranging from around 1,200 feet to more than 7,900 feet, it’s a route that demands respect and attention from those behind the wheel.

Flora, Fauna, and Natural History: A Biodiversity Hotspot
Beyond geology and history, the San Gabriel Mountains are a treasure trove of biodiversity. The montane environment, with its varied elevation and climate zones, has given rise to a rich tapestry of flora and fauna. Iconic trees like the Jeffrey pine, Coulter pine, and California black oak adorn the landscape. Wildflowers paint the meadows in vibrant hues, from the golden yarrow to the scarlet larkspur.

The fauna is just as diverse, with animals like the California condor, bighorn sheep, and mountain lions roaming the rugged terrain. The waters that trickle and rush down these mountains are home to arroyo chubs and Santa Ana suckers.

The California condor is known to inhabit the San Gabriel range

Protection of this vital ecosystem came in the form of the San Gabriel Mountains National Monument designation in 2014, ensuring that the mountains’ rich biodiversity and cultural significance will be preserved for generations.

The San Gabriel Mountains are more than just a scenic backdrop. They reflect the Earth’s active geology, hold key historical moments, and support diverse ecosystems. Amid growing urbanization, these mountains remain a lasting reminder of the interconnectedness of life, history, and natural forces.

The Sweet Journey of the Boysenberry from Family Farms to Theme Park Fame

Bowl of boysenberries on wooden table.

California has long been a hub for berry innovation, boasting a rich history of developing countless berry cultivars. While it’s tough to pin down an exact number, the state’s contributions span a wide range of fruits, from strawberries to blackberries to loganberries, raspberries, and even blueberries.

Somewhere in the pantheon of berries, tucked between the familiar blackberry and the enigmatic lingonberry (a Scandinavian staple, just ask the Swedes, or swing by IKEA), you’ll find the boysenberry. With its deep maroon color, plump size, and a flavor that dances between sweet and tart, the boysenberry is a delicious emblem of California’s horticultural creativity. (Who knew we needed yet another berry?) But how did this berry come to be, and what’s the story behind a Southern California amusement park helping to make it famous?

The journey of the boysenberry begins with its namesake, Rudolph Boysen. In the early 1920s, Boysen, a curious California-based farmer and horticulturist, began experimenting with berry plants at his home in Napa, California. His objective? To develop a new hybrid berry that combined the best attributes of the European raspberry, blackberry, American dewberry, and loganberry.

Rudolph Boysen

On relocating to Orange County, he didn’t leave his passion behind; instead, he brought along his precious berry vines, planting them on his in-law’s property in Anaheim, which at that time was a relatively unpopulated expanse dominated by vast orange and lemon groves, interspersed with small farms and ranches. 

Between 1921 and 1950, Boysen dedicated his professional life to serving as the Anaheim City Parks superintendent. His persistent efforts bore fruit (ha) in 1923 when his hybrid successfully grafted and flourished. However, while Boysen was successful in creating the berry, he faced challenges in cultivating it on a larger scale. Some years after his initial success, a near-fatal accident sidelined him, and his boysenberry plants began to wither, seemingly destined for obscurity.

Enter Walter Knott, another farmer with an insatiable curiosity and a healthy dose of ambition,. Upon discovering that Boysen had given up his cultivation experiments and sold his property, Knott went in search of the delicious berry. Accompanied by  George M. Darrow of the USDA, the duo ventured to Boysen’s former farm. There, amidst an overgrowth of weeds, they discovered a few withering vines clinging to life. Determined to give these vines a new lease on life, they carefully relocated them to Knott’s farm in Buena Park, California. With diligent care and attention, Knott revived these plants, enabling them to thrive and produce fruit once again. As a result, Walter Knott became the pioneering figure in the commercial cultivation of the berry in Southern California. Knott learned about Boysen’s creation and, understanding its potential, sought out the remaining withered vines.

Knott’s Berry Farm

With a blend of horticultural expertise and an entrepreneur’s spirit, Knott not only rescued the dying boysenberry vines but also began cultivating and selling the berries on his own farm, which was located in Buena Park, California.

As the berries grew in popularity, so did Knott’s business. By the 1940s, Knott’s farm had transformed into a bustling destination, offering visitors not just the chance to buy fresh boysenberries and boysenberry products, but also to experience the charm of a recreated ghost town and other attractions. As the business evolved, it gave birth to what is now known as Knott’s Berry Farm, one of the most popular amusement parks in Southern California.

Today, it’s a full-blown amusement park with high-speed roller coasters like GhostRider, a massive wooden coaster, and Silver Bullet, a looping steel ride that twists over the park’s lake. The Timber Mountain Log Ride, one of the park’s most beloved attractions, simulates a journey through a 19th-century logging camp, complete with animatronic lumberjacks and sawmills. It’s a tribute to the massive wooden flumes that loggers once built to move timber from deep in the forest down to the mills and markets. One of the largest of these flumes was at Converse Basin, once home to the biggest contiguous grove of giant sequoias on Earth. That same area became the site of one of the most devastating logging operations in American history, where thousands of ancient sequoias—some millenia old—were cut down in the rush to harvest timber. We did a story about it you can read here. It’s a sobering reminder of how quickly early California’s natural wonders were exploited in the name of progress.

But back to Boysenberries. Let’s finish this one up, shall we?

Biologically, the boysenberry is a testament to the wonders of plant hybridization, showcasing the ability to combine distinct plant species to produce something entirely new. And tasty. The boysenberry isn’t just a product of careful crossbreeding, it’s a classic California story of perseverance, partnership, and a dose of luck. Sunshine helps too. It’s about how a nearly forgotten berry was saved from obscurity by two determined farmers and went on to become a symbol of California itself, thanks in part to the magic of an amusement park.

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Einstein in Pasadena: Three Wonderful Winters in Paradise

Einstein at the Santa Barbara home of Caltech trustee Ben Meyer on Feb. 6, 1933.
(The Caltech Archives)

“Here in Pasadena, it is like Paradise. Always sunshine and clear air, gardens with palms and pepper trees and friendly people who smile at one and ask for autographs.” – Albert Einstein (U.S. Travel Diary, 1930-31, p. 28)

Albert Einstein is often associated with Princeton, where he spent his later years as a towering intellectual figure, and with Switzerland, where he worked as a young patent clerk in Bern. It was in that spartan, dimly lit office, far from the great universities of the time, that Einstein quietly transformed the world. In 1905, his annus mirabilis or “miracle year,” he published a series of four groundbreaking papers that upended physics and reshaped humanity’s understanding of space, time, and matter. With his insights into the photoelectric effect, Brownian motion, special relativity, and the equivalence of mass and energy (remember E=mc2?), he not only laid the foundation for quantum mechanics and modern physics but also set in motion technological revolutions that continue to shape the future. Pretty good for a guy who was just 26.

Albert Einstein spent his later years as a world-famous scientist traveling the globe and drawing crowds wherever he went. His letters and travel diaries show how much he loved exploring new places, whether it was the mountains of Switzerland, the temples of Japan, or the intellectual circles of his native Germany. In 1922, while on his way to accept the Nobel Prize, he and his wife, Elsa, arrived in Japan for a six-week tour, visiting Tokyo, Kyoto, and Osaka.

But of all the places he visited, one city stood out for him in particular. Pasadena, with its warm weather, lively culture, and, most importantly, its reputation as a scientific hub, had a deep personal appeal to Einstein. ​He visited Pasadena during the winters of 1931, 1932, and 1933, each time staying for approximately two to three months. These stays were longer than many of his other travels, giving him time to fully immerse himself in the city. He spent time at Caltech, exchanging ideas with some of the brightest minds in physics, and fully embraced the California experience, rubbing elbows with Hollywood stars (Charlie Chapman among them), watching the Rose Parade, and even tutoring local kids. Einstein may have only been a visitor, but his time in Pasadena underscores how deeply rooted science was in the city then, and how strongly that legacy endures today. Pasadena remains one of the rare places in the country where scientific inquiry and creative spirit continue to thrive side by side. Pasadena was among the earliest cities to get an Apple Store, with its Old Pasadena location opening in 2003.

Einstein’s residence at 707 South Oakland Avenue in Pasadena, where he stayed his first winter in California (CalTech Archives)

Few scientists have received the public adulation that Einstein did during his winter stays in Pasadena. As a hobbyist violinist, he engaged in one-on-one performances with the conductor of the Los Angeles Philharmonic. Local artists not only painted his image and cast him in bronze but also transformed him into a puppet figure. Frank J. Callier, a renowned violin craftsman, etched Einstein’s name into a specially carved bow and case.

During his first winter of residence in 1931, Einstein lived in a bungalow at 707 South Oakland Avenue. During the following two winters, he resided at Caltech’s faculty club, the Athenaeum, a faculty and private social club that is still there today.

Yet, the FBI was keeping a watchful eye on Einstein as well. He was one of just four German intellectuals, including Wilhelm Foerster, Georg Nicolai, and Otto Buek, to sign a pacifist manifesto opposing Germany’s entry into World War I. Later, Einstein aligned himself with Labor Zionism, a movement that supported Jewish cultural and educational development in Palestine, but he opposed the formation of a conventional Jewish state, instead calling for a peaceful, binational arrangement between Jews and Arabs.

In front of the Athenaeum Faculty Club, Caltech, 1932. 
(Courtesy of the Caltech Archives.)

After his annus mirabilis in 1905, Einstein’s influence grew rapidly. In 1919, his theory of relativity was confirmed during a solar eclipse by the English astronomer Sir Arthur Eddington. The announcement to the Royal Society made Einstein an overnight sensation among the general public, and in 1922, he was awarded the 1921 Nobel Prize in Physics. While teaching at the University of Berlin in 1930, Arthur H. Fleming, a lumber magnate and president of Caltech’s board, successfully persuaded him to visit the university during the winter. The visit was intended to remain a secret, but Einstein’s own travel arrangements inadvertently made it public knowledge.

Einstein speaking at the dedication of the Pasadena Junior College (now PCC) astronomy building, February 1931. 
(Courtesy of the Caltech Archives)

After arriving in San Diego on New Year’s Eve 1930, following a month-long journey on the passenger ship Belgenland, Einstein was swarmed by reporters and photographers. He and his second wife, Elsa, were greeted with cheers and Christmas carols. Fleming then drove them to Pasadena, where they settled into the bungalow on S Oakland Ave.

Albert Einstein and his violin (Caltech Archives)

During their first California stay, the Einsteins attended Charlie Chaplin’s film premiere and were guests at his Beverly Hills home. “Here in Pasadena, it is like Paradise,” Einstein wrote in a letter. He also visited the Mt. Wilson Observatory high in the San Gabriel Mountains. Einstein’s intellectual curiosity extended far beyond his scientific endeavors, leading him to explore the Huntington Library in San Marino, delighting in its rich collections. At the Montecito home of fellow scientist Ludwig Kast, he found comfort in being treated more as a tourist than a celebrity, relishing a brief respite from the spotlight.

In Palm Springs, Einstein relaxed at the winter estate of renowned New York attorney and human rights advocate Samuel Untermeyer. He also embarked on a unique adventure to the date ranch of King Gillette, the razor blade tycoon, where he left with a crate of dates and an intriguing observation. He noted that female date trees thrived with nurturing care, while male trees fared better in tough condition: “I discovered that date trees, the female, or negative, flourished under coddling and care, but in adverse conditions the male, or positive trees, succeeded best,” he said in a 1933 interview.

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Not exactly relativity, but a curiosity-driven insight reflecting his ceaseless fascination with the world.

During his three winters in Pasadena, Einstein’s presence was a source of intrigue and inspiration. Students at Caltech were treated to the sight of the disheveled-haired genius pedaling around campus on a bicycle, launching paper airplanes from balconies, and even engaging in a heated debate with the stern Caltech president and Nobel laureate, Robert A. Millikan, on the steps of Throop Hall. Precisely what they debated remains a mystery. (Maybe something about the dates?)

Einstein with Robert A. Millikan, a prominent physicist who served as the first president of Caltech from 1921 to 1945 and won the Nobel Prize in Physics in 1923. (Courtesy of the Caltech Archives.)

During his final winter in California, a near-accident led the couple to move into Caltech’s Athenaeum. His suite, No. 20, was marked with a distinctive mahogany door, a personal touch from his sponsor, Fleming. In 1933, as Nazi power intensified in Germany, Einstein began searching for a safe place to continue his work. Although Caltech made an offer, it was Princeton University‘s proposal that ultimately won him over. Einstein relocated to Princeton that same year, where he played a significant role in the development of the Institute for Advanced Study and remained there until his death in 1955.

Suite No. 20, Einstein’s mahogany door at the Caltech Athenaeum

Today, a large collection of Einstein’s papers are part of the Einstein Papers Project at Caltech. And Einstein’s suite at Caltech’s Athenaeum, still displaying the mahogany door, serves as a physical reminder of his visits.

During his third and final visit to Caltech in 1933, Hitler rose to power as Chancellor of Germany. Realizing that, as a Jew, he could not safely return home, Einstein lingered in Pasadena a little longer before traveling on to Belgium and eventually Princeton, where he received tenure. He never returned to Germany, or to Pasadena. Yet he often spoke fondly of the California sunshine, which he missed, and in its own way, the sunshine seemed to miss him too.

Hannes Keller’s Deadly 1,000-Foot Descent off Catalina Island Was the Dive of the Century

An ambitious quest for underwater exploration that ended in tragedy beneath the Pacific waves.

The city of Avalon on Catalina Island (Erik Olsen)

In 1962, Swiss physicist and deep-sea diving pioneer Hannes Keller embarked on an ambitious and perilous mission to push the boundaries of human endurance and underwater exploration. California, with its dramatic coastline and history of daring maritime ventures, became the setting for this bold effort to make history in diving. Partnered with British diver and journalist Peter Small, Keller aimed to descend inside a specially designed diving bell named Atlantis to an unprecedented depth of 1,000 feet off the coast of Catalina Island. Their plan involved exiting the pressurized diving bell once it reached the ocean floor, a groundbreaking and dangerous procedure that would allow them to perform tasks outside in the extreme depths. What promised to be a historic achievement, however, took a tragic turn.

Keller’s passion for deep-sea diving had recently garnered international attention, fueled by his record-breaking dives and groundbreaking research into advanced breathing gas mixtures. Working alongside Dr. Albert Bühlmann, a renowned physiologist specializing in respiration, Keller employed cutting-edge technology, including an IBM computer, to meticulously design gas formulas that could counteract the dangers of deep diving. Their innovative work addressed the twin challenges of nitrogen narcosis and decompression sickness, promising to revolutionize underwater exploration.

For Keller, diving was initially an unconventional pursuit. He was engaged in teaching mathematics to engineering students in his native town of Winterthur, close to Zurich, and had aspirations to become a pilot. However, the prohibitive cost of flying on a teacher’s salary led him to explore other avenues. Introduced to the burgeoning sport of scuba diving by a friend in the late 1950s, Keller applied his mathematical and scientific acumen to the field. He soon concluded that the existing techniques in deep-sea diving were outdated and ripe for revolutionary advancement.

“If a man could go, for instance, to 1,000 feet down and do practical work,” Mr. Keller wrote in The Sydney Morning Herald, “then all the continental shelf zone could be explored, a total of more than 16 million square miles.”

Keller prepares for his May 1961 chamber dive at the United States Navy Experimental Diving Unit (NEDU). Photo: US Navy

Keller and Bühlmann worked collaboratively to expand their computerized concoction of breathing gases, ultimately selecting a dive site off near Avalon Bay at Catalina Island in Southern California. This location was chosen due to its dramatic underwater geography, where the ocean floor descends sharply from the coast into the deep ocean.

At the time, it was widely believed that no human being could safely dive to depths beyond three hundred feet. That was because, beginning at a depth of one hundred feet, a diver breathing normal air starts to lose his mind due to nitrogen narcosis.

Partnering with Peter Small, co-founder of the British Sub Aqua Club, Hannes Keller planned their historic descent using a specially designed diving bell named Atlantis. This advanced pressurized chamber, deployed from a surface support vessel, was staffed by a skilled technical crew tasked with monitoring gas levels and maintaining constant communication with the divers through a surface-to-bell phone link. The Atlantis diving bell represented a significant leap in underwater technology, providing a controlled environment that allowed divers to venture into previously unreachable depths. Its design and operational success revolutionized the field of deep-sea exploration, offering invaluable insights into human physiology under extreme pressure and laying the groundwork for future advancements in underwater science and technology.

Keller’s experimental dives piqued the interest of the U.S. Navy, as they saw the potential to revolutionize diving safety and practicality. If proven successful, Keller’s methods could transform existing dive tables and enable safer, more practical deep-sea exploration. Encouraged by the promising outcomes of Keller’s preliminary chamber tests and several less extreme open-sea trials, the Navy allowed him to perform a test dive at their primary experimental facility, adjacent to the Washington dive school. They also became a financial supporter of Keller’s ambitious thousand-foot dive.

To carefully scrutinize the operation, the Navy designated Dr. Robert Workman, one of their foremost decompression specialists, to be present on site. A few days after reaching Catalina in late November, Dr. Workman joined Dr. Bühlmann, the rest of Keller’s team, and various onlookers aboard Eureka, an experimental offshore drilling vessel provided by Shell Oil Co. Shell, like other oil and gas enterprises, had a vested interest in innovative techniques that could enhance the productivity of commercial divers. If the dive was successful, the company would receive Keller’s secret air mixture technology and thereby become an instant frontrunner in offshore oil exploration. Their interest was particularly relevant as offshore drilling initiatives were venturing into deeper waters, both off the California shore and in the Gulf of Mexico.

Resembling a huge can of soup, Atlantis stood seven feet tall and had a diameter slightly greater than four feet. Its structure featured an access hatch at the bottom and was adorned with an array of protruding pipes and valves, adding to its industrial appearance.

British journalist Peter Small (BSAC)

As a journalist, Peter Small intended to pen a first-hand narrative of the groundbreaking dive. On December 1, as part of a final preparatory dive, Small and Keller were lowered inside Atlantis to a depth of three hundred feet, where they spent an hour scuba diving outside the bell. During the decompression process within the bell, both divers experienced relatively mild symptoms of decompression sickness, commonly known as the bends. Keller felt the effects in his belly, while Small was afflicted in his right arm. Decompression sickness is still a relatively poorly understood phenomenon, and it remains unpredictable as to which part of the body it might affect.

Keller’s symptoms abated on their own that night, but Small’s discomfort lingered until he underwent recompression treatment. Despite this warning sign, Keller was determined to continue with the dive as planned, without conducting further incremental tests at increasing depths before the ambitious thousand-foot descent. His decision was likely influenced, at least in part, by the assembled crowd of journalists and other spectators eager to witness the historic dive. The constraints of time, finances, and equipment availability added to the pressure, compelling the team to proceed with the experimental dive as scheduled.

The diving bell Atlantis is lifted out of the water after Keller and the journalist Peter Small descended 1,020 feet to the Pacific Ocean floor in December 1962.

On Monday, December 3, around noon, Atlantis began its descent beneath the surface of the Pacific, enclosing its two divers within. The journey towards the ocean floor took under thirty minutes. Upon reaching the target depth of a thousand feet, a series of dark and chaotic moments ensued. Keller exited the bell to plant a Swiss flag and an American flag on the ocean floor. In the process, his breathing hoses became entangled with the flags, and after clambering back inside Atlantis, he lost consciousness.

The gas mixture had somehow become compromised. Peter Small also blacked out, despite never having left the diving bell. As Atlantis was hastily ascended to within two hundred feet of the surface, several support divers swam down to meet the bell. Tragically, one of these support divers, Christopher Whittaker, a young man of just nineteen, disappeared without a trace.

Pacific Ocean off Catalina Island (Erik Olsen)

Keller came to roughly a half-hour after the incident, and Small regained consciousness, but it took nearly two hours for him to do so. Upon awakening, Small engaged Keller in coherent questions about what had transpired. He reported feeling cold and, although he retained the ability to speak, see, and hear, he could not feel his legs. Despite not experiencing any pain, he was too weak to stand. Leaning against his Swiss counterpart, he drifted off to sleep as their decompression within the bell continued.

Several hours later, as Atlantis was being transported back to shore to Long Beach from the dive site near Catalina, Keller discovered that Small had ceased breathing and had no pulse. Desperate to revive him, Keller administered mouth-to-mouth resuscitation and cardiac massage, but to no avail. Small was cold and pallid. The remaining pressure inside the bell, about two atmospheres, was hastily released in a frantic effort to get Small to a hospital after being trapped inside Atlantis for eight hours. Tragically, upon arrival, he was promptly pronounced dead.

The Atlantis diving bell (Paul Tzimoulis)

The Los Angeles County coroner identified the cause of death as decompression sickness. An examination revealed that Small’s tissues and organs were filled with Nitrogen gas bubbles. However, Keller contended that other factors, such as a potential heart attack and the panic Small displayed upon reaching the thousand-foot mark, contributed to the tragedy.

Regardless of the underlying causes, the catastrophic dive to thirty atmospheres and the loss of two lives led to a rapid waning of interest in Keller’s previously sensational methods. The potential for failure of this magnitude had been a concern to many in the deep diving community and the day’s events set back research in the emerging field of saturation diving. Even before this event, saturation diving had only tepid support from the Navy, but this made some people loss faith in the technique. Of course, it would not be the end of saturation diving, not by a long shot. 

Hannes Keller in his later years. (Credit: Keller, Esther, Niederglatt, Switzerland)

Modern deep-water diving owes much to the groundbreaking experiments of Hannes Keller. His historic dive to 1,020 feet (311 meters) off Catalina Island was a remarkable achievement that captivated the world. Far from being a mere stunt, as some critics claimed, Keller’s dive was a meticulously planned scientific endeavor designed to push the boundaries of human exploration of the ocean depths. This Swiss adventurer’s pioneering work laid the foundation for advances in deep-sea diving techniques, leaving an enduring legacy in the field.

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Christopher Swann, a diving historian, said the dive “was a milepost in the sense that it was the first time something like that had been done.”

Keller ended up living a rich and long life, dying on December 1, 2022, at at a nursing home in Wallisellen, Switzerland, near his home in Niederglatt. He was 88.

J. Robert Oppenheimer: The Berkeley Era and The Birth of the Manhattan Project

With the release of the movie Oppenheimer, it’s worth taking a look at the role that California played in one of the most important technological developments of the 20th century: the making of the atomic bomb. The Manhattan Project, the prodigious scientific endeavor that produced the world’s first nuclear weapons, cast a long, dark shadow over the mid-20th century. But amid the mushroom clouds, there lies a tale of innovation and scientific genius that originated from an unlikely source—the University of California, Berkeley.

The film team filmed several scenes at Berkeley, adding a vintage car and 1940s-era lampposts to the campus. Oppenheimer taught at UC Berkeley from 1929 to 1943 — his office was on the third floor of Physics North (then named LeConte Hall) 

For years, America’s physics powerhouse resided in the East. But in the post-WWI era, the western horizon blazed with opportunity. Visionary administrators at Caltech and UC Berkeley threw financial muscle behind their bold mission: to make physics research a priority.

By the dawn of the 1930s, their investments bore fruit. The American Physical Society‘s president hailed California as a hotbed of physics innovation, equating it with the East in the academic landscape of the discipline. Universities played high-stakes poker for the talents of up-and-coming physicists like Oppenheimer and Ernest Lawrence, known for his groundbreaking work in photoelectricity and ionization.

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J. Robert Oppenheimer, one of the leading physicists of the 20th century, is often remembered as the ‘father of the atomic bomb’. However, his journey toward this formidable title began at Berkeley, an intellectual crucible where his talent for theoretical physics was honed, ultimately leading him to oversee the Manhattan Project, a scientific endeavor that would change the world.

J. Robert Oppenheimer, Enrico Fermi and Ernest O. Lawrence at UC Berkeley in 1940. Courtesy: Lawrence Berkeley National Laboratory

Oppenheimer’s relationship with Berkeley began in 1929 when he joined as an Assistant Professor of Physics. This was an exciting period in the realm of science. Quantum mechanics was in its infancy and a new breed of scientists was emerging, eager to unlock the secrets of the universe. Oppenheimer, with his insatiable curiosity and infectious enthusiasm, was just the right person for this time of exploration.

During his years at Berkeley, Oppenheimer made significant contributions to quantum mechanics, notably his work on the Oppenheimer-Phillips process. This theory describes a particular type of nuclear reaction that occurs during the absorption of a neutron by a nucleus, an understanding that would later prove pivotal to the development of nuclear energy.

Outside the laboratory, Oppenheimer was an adored figure, known for his quick wit and charismatic teaching style. He was instrumental in building the physics program at Berkeley into perhaps the finest in the country by attracting some of the brightest minds of the time. Together, they would be known as dubbed the “luminaries”.

J. Robert Oppenheimer (Ed Westcott/U.S. Department of Energy via Bay City News)

“The group met secretly in his office at the northwest corner of the top floor of ‘old’ LeConte Hall. This office, like others on the top floor, has glass doors opening out onto a balcony,” wrote Raymond T. Birge, former chair of the Berkeley physics department at the time. “This balcony is readily accessible from the roof. To prevent this method of entry, a very heavy iron netting was placed over the balcony. A special lock was placed on the door to the office and only Oppenheimer had the key. No janitor could enter the office, nor could I, as chairman of the department,”

Hans Bethe, one of the great German-American theoretical physicists of the age said Oppenheimer established UC Berkeley as the “greatest school of theoretical physics the United States has ever known.”

Although he was increasingly recognized as a pivotal figure in theoretical physics, former students say he remained accessible, consistently urging his students to question norms and extend limits. He actively promoted a culture of inquiry among his students, even if his responses occasionally seemed harsh. However, Oppenheimer’s questions to his student speakers were meant to clarify rather than to humiliate, often aimed more at enlightening the audience than himself. His rapport with his students was unexpectedly casual. He provided an open-door policy, inviting his students to visit his office anytime to utilize the physics resources within his personal collection.

J. Robert Oppenheimer with Glenn T. Seaborg and Ernest O. Lawrence in early 1946. (Photo courtesy of Berkeley Lab)

Oppenheimer’s life at Berkeley wasn’t all physics. A man of varied interests, he was an avid hiker, horseback rider, and aficionado of literature, poetry, and art. These varied interests made him a multifaceted character and helped him foster connections with many prominent figures across different fields. His unique combination of scientific genius, humanity, and leadership qualities made him a standout candidate for the enormous task that lay ahead – the Manhattan Project.

While no major Manhattan Project facilities graced the Golden State, Berkeley, nestled in the heart of California, emerged as an unsung hero of the project. Berkeley offered more than a tranquil academic setting; it provided an assembly line of experts that would revolutionize nuclear science. Not only was Berkeley home to Oppenheimer the university also attracted other nuclear-era luminaries like Ernest Lawrence, and chemists Glenn Seaborg.

Berkeley had always been special. California’s first land-grant university, founded in 1868, Berkeley underwent a metamorphosis under the leadership of Robert Sproul. From 1930 to 1958, Sproul spearheaded the transformation of Berkeley into a hub of intellectual firepower. The University of California system burgeoned across the state, with Berkeley, the original campus, earning a reputation as one of the nation’s foremost research institutions. Its powerhouse physics department became a beacon in the dark world of the Manhattan Project.

Berkeley’s list of accomplishments in physics is long and distinguished, but one discovery stands out – the identification of plutonium. Edwin McMillan, a promising physicist at Berkeley, ventured into the wilderness of uranium fission products. In 1940, he stumbled upon an unknown substance – element 93, or as he named it, “neptunium,” a hat tip to the distant planet Neptune. McMillan predicted that neptunium decayed into plutonium, the elusive element 94.

Glenn Seabord – Wikipedia

Glenn Seaborg, another Berkeley savant, picked up where McMillan left off when the latter migrated east to work at MIT. Seaborg unveiled the heart of plutonium, exposing its fundamental chemical and nuclear properties, including its high propensity for fission. As the world’s leading expert on plutonium, Seaborg directed the ambitious effort to separate plutonium from uranium and other reactor products.

Meanwhile, Ernest Lawrence led a research group that broke boundaries with the cyclotrons at the Rad Lab. They used the 60-inch cyclotron to bombard uranium with neutrons, producing plutonium for scrutiny. But Lawrence had a revelation. In 1941, he realized the cyclotron could also operate as a mass spectrometer, effectively isolating uranium-235 from uranium-238. This technique was later adopted at Oak Ridge’s Y-12 Separation Plant, enabling large-scale separation. The cyclotron, rechristened as a “Calutron” in a nod to the University of California, had revolutionized nuclear science.

Recording of the “Rainier” shot, Nevada Test Site, Sept. 19, 1957.
Atomic Energy Commission/U.S. Department of Energy via Wikipedia Commons

While these figures were all played prominent roles in the development of the atomic bomb dropped on Hiroshima and Nagasaki in 1945, it is Oppenheimer who is best remembered. After fourteen years at Berkeley, Oppenheimer was plucked from the physics department at Berkeley by General Leslie Groves to assume leadership of the research program at Los Alamos. Even after his move, Oppenheimer fostered a close alliance between Berkeley and the Manhattan Project. In a shroud of secrecy, the University of California took on the management of the operations at Los Alamos. The university even set up a Los Angeles office that handled material logistics for the lab.

Despite decades passing and the veils of secrecy lifting, the legacy endures. The Los Alamos lab continues to operate under the University of California’s management, preserving Berkeley’s indelible imprint on the atomic age. It’s a testament to the institution’s groundbreaking contributions and a tribute to the remarkable scientists who once walked its hallowed halls.

Maybe You’ve heard of Josiah Whitney, Mt. Whitney’s Namesake

Mount Whitney, the highest mountain in the contiguous United States, is one of the great peaks in California. A wildly popular destination for hikers, climbers, and backpackers, Whitney is located in Inyo National Forest and Sequoia National Park, California.

But how did Mt. Whitney get its name?

“The culminating peak of the Sierra” was identified in 1864 by a team from the California Geological Survey and named Mount Whitney in honor of the team’s leader, State Geologist Josiah Whitney. During that same expedition, survey member Clarence King made two attempts to reach the summit but did not succeed.

But Whitney wasn’t the mountain’s only name. When a group of fishermen made the first recorded ascent in 1873, they called it “Fisherman’s Peak,” a name that stuck locally for some time before Mount Whitney became the official designation. Long before that, the Indigenous Paiute people called the mountain Too-man-i-goo-yah, meaning “the very old man” or “the guardian spirit,” reflecting its towering presence and cultural significance.

Josiah Dwight Whitney was an American geologist and surveyor who made significant contributions to the field of geology in California. Born in Northampton, Massachusetts, in 1819, Whitney became interested in science at an early age and studied geology and mineralogy at Yale University. In 1860, he was appointed the State Geologist of California and founded the California Geological Survey, one of the oldest geological surveys in the nation.

Because gold fever still gripped much of the world at that time, most people assumed Whitney’s work would focus on locating valuable mineral resources, but Whitney instead pursued a broader scientific agenda—paleontology, historical geology, petrology, stratigraphy, and tectonics. He delivered meticulous studies of mineralogy and placed California’s geology within a global framework, prioritizing knowledge over immediate economic gain. The state, unimpressed by his academic approach, eventually cut his funding.

Whitney’s work in California was groundbreaking and helped establish the state as a hub of geological research. He conducted extensive surveys of the state’s natural resources, including minerals, soils, and water sources. He was also instrumental in mapping the state’s topography and geology, including the Sierra Nevada mountain range, where he made several important discoveries.

One of Whitney’s most significant contributions to California’s geology was the discovery of the existence of glacial action in the Sierra Nevada mountains. In 1864, he published a report describing the glacial formations he had observed in the mountains, including the formation of Yosemite Valley, which he attributed to the action of glaciers. This report was groundbreaking at the time and helped establish the study of glacial geology as a major area of research.

In addition to his work as a geologist, Whitney was also a skilled surveyor and cartographer. He was responsible for creating some of the first accurate maps of California, which were used by explorers, settlers, and scientists alike. His maps were highly detailed and included information about the state’s geology, topography, and natural resources.

Photo of the author at the top of Mount Whitney (Heidi Schumann for the New York Times)

In 1875, Whitney was elected to the National Academy of Sciences, and in 1880, he was awarded the Wollaston Medal by the Geological Society of London. Perhaps the most enduring recognition of his work is the fact that the highest peak in the contiguous United States is named after him. Mount Whitney, which stands at 14,505 feet, was named in his honor in 1896.

Whitney’s legacy lives on through the California Geological Survey, which he founded and served as its first director. The survey played an important role in the development of California, providing valuable information about the state’s natural resources and geology. It continues to operate today, providing information and expertise to policymakers, scientists, and the public.