Travels in Geology: Walking toward Whitney: A journey through the Sierra High Country along the John Muir Trail

Views astound along much of the John Muir Trail.


Kate Prengaman

The John Muir Trail (JMT) begins — or ends, in the author’s case — on Mount Whitney. The author, Kate (right), and her hiking companion, Joanna, pose at the trail sign.


Kate Prengaman

The climb to reach the Palisades Lakes (shown here) below Mather Pass is known as the Golden Staircase. It was the last piece of the trail completed in 1938.


Kate Prengaman

From atop Mount Whitney — the tallest peak in the lower 48 states — ridge upon ridge of Central California’s Sierra Nevada range stretches out before you, the topography blurring into the northern horizon. My travel companion and I arrived at Mount Whitney’s peak after a 340-kilometer hike through the High Sierras along the John Muir Trail (JMT) — climbing up and down many of the ridges that now fade in the distance. Having just traversed the trail, one boot-step at a time, you can appreciate the scale of the scenery all the more: You’ll understand just how high you truly are and that those ridges, their severity now softened by distance, are anything but tame.

The trail is named for naturalist John Muir, whose writings on the Sierra Nevada championed wilderness conservation and helped birth the environmental movement in the late 19th century. A hike along the trail is a tour of the granite and glacial geology of the Sierra Nevada. The range was built by 2 million years of recent uplift, which followed millions of years of shifting plates and volcanic activity that built its foundation.

The hike to Mount Whitney traverses uninterrupted wilderness through three national parks — Sequoia, Kings Canyon and Yosemite — as well as national wilderness areas such as the Ansel Adams Wilderness and 13 different river drainages over which the ecosystems and geology continually shift. The trail brings you views of the imposing Ritter Range, the columnar-jointed basalt of Devils Postpile, red cinder cones and Yosemite’s iconic exfoliated domes. It’s not for the faint of heart (or the weak-kneed), but if you can make time for it, it’s a trip you’ll never forget.

A Steep Start

The traditional route along the JMT starts by heading straight up Mount Whitney and then continues northward toward Yosemite. But beginning at Yosemite and heading south, saving the tallest climbs for last, is considered easier and is the far more popular route today. In truth, there is no easy way to complete this traverse of the High Sierras. On our August 2013 trip, my friend Joanna and I opted for the latter route, hoping that finishing with Mount Whitney would offer a captivating climax for the trip and would ensure we’d be in better climbing shape by the time we reached the tallest passes.

The first climb out of Yosemite Valley, on the popular route to Nevada Falls and Half Dome, rises 610 vertical meters over 4.8 kilometers. We started from an alternate trailhead along the park’s Glacier Point Road, adding a few extra kilometers but saving ourselves some elevation gain — a worthwhile tradeoff in our estimation. Considering an alternate trailhead might make it easier to get permits for your first choice dates as well (see sidebar).

We jumped onto the true JMT at Nevada Falls. The waterfall is usually roaring as Sunset Creek drops about 180 meters, but last year was so dry that the creek simply slid quietly over the falls. This first part of the trail can be a bit crowded, and until you pass Half Dome, one of the park’s most iconic peaks, your heavy packs will look out of place among the lighter daypacks of short-term tourists. The present guise of Half Dome’s giant granite face was formed by exfoliation — the cracking and peeling of layers of granite unburdened by erosion as the peak was uplifted. This is dome country, the rounded peaks visible all around you from many viewpoints, but Half Dome dominates.

If you want to summit the peak, plan ahead and secure the necessary permits. Hauling yourself up the dome, using the bolted-in cable handrails that enable nontechnical climbers to scale the sheer face, is exhilarating, but the experience is daunting and not for those with acrophobia. Don’t even think about taking your heavy packs.

Beyond Half Dome, the JMT keeps climbing up to Sunrise Camp and Cathedral Pass. Just kilo­meters from the day-hiking masses, there’s a surprising amount of solitude to be found in the ascent. Cathedral Lakes are the reward for your effort. They are just the first of dozens of shimmering alpine lakes that beckon you to camp near their shores, soak your sore feet in clear, cold water, and take photographs that never quite capture the true beauty of the steep peaks guarding them.

Shortly after exiting Yosemite to the south, the glacier-carved granite abruptly disappears, replaced by the darker volcanic Ritter Range, which stands imposingly above Thousand Island Lake. Much older than the surrounding granite formations, these craggy peaks are remnants of the ancient Minaret Caldera.

The trail descends and traverses through even older rocks — metamorphosed volcanic breccias, tuffs and colorful conglomerates whose beautiful and varied patterns and inclusions are enough to hold your attention for days, if you didn’t have to keep moving on toward your next food resupply.

A Wilderness Mindset

And so it continues, day after day. Break camp. Hike. Gawk at the scenery. Climb. Descend. Gawk again. Make camp. Cook. Eat. Stargaze. Sleep. Repeat. You develop a rhythm, but somehow, every day, the scenery gets better and better.

About a week in, you reach Devils Postpile, just outside Mammoth Lakes. The official JMT remains in the wilderness, skirting the national monument and the tourists, campground and lodge where you can resupply and buy an expensive shower. But most hikers take the brief detour, for the resupply or the geology or both. Devils Postpile is a formation of columnar jointed basalt that fractured into nearly perfect hexagonal columns about 100,000 years ago as a lava lake cooled and contracted. Erosion has taken its toll over time, with freeze-thaw cycles shattering some columns and others being toppled by earthquakes. The broken hexagonal bits form a talus slope below. As you return to the trail after your detour, you pass another unique volcanic spot, the Red Cones, and a trail covered in reddish-brown pumice, formed when the cinder cones erupted about 5,000 years ago.

Continuing on, you soon return to the more familiar glacier-carved granite landscape. Just over halfway through the trip, the trail climbs up to a hanging valley. A steep set of switchbacks then takes you to Evolution Basin, which features smooth granite slabs, deeply carved lakes that are home to the plump, endangered mountain yellow-legged frog, and tall, rough peaks, untouched by the glaciers, including Mount Mendel and Mount Darwin, named for the behemoths of genetics and evolutionary theory. The basin was scoured, and little soil has formed here.

Climbing past the lakes full of the fat frogs and up over Muir Pass, the geology again shifts dramatically into the black peaks of the Ionian Basin. You then skirt the massive metamorphic region known as the Goddard Terrane, which formed between 250 million and 150 million years ago when colliding continental plates kicked off a flurry of volcanic activity. Later tectonic movement metamorphosed the granite into the dark rocks seen today. 

The trail continues, up and down, up and down. There’s not much flat terrain on this trip, especially in the second half. The climb to each high pass has its own character, its own geology, and its own vast view of the landscape. The scenery is impressive, but so is the fact that this well-constructed trail is here at all.

Construction of the trail, named in honor of the man who introduced the country to the beauty of the Sierras and led the political push to designate areas of wilderness, began in 1915, the year after his death. Theodore Solomons, an explorer and naturalist a generation younger than Muir, dreamed up the crest trail as a teenager and spent years scouting out potential routes. The trail was finally finished in 1938 with the addition of the climb from the South Fork of the Kings River up to Mather Pass, a climb known as the Golden Staircase. The tight switchbacks rise 450 meters over a steep wall between the river valley and the Palisades Lakes below the barren talus. When hiking it today, especially when stopped on one of the dozens of switchbacks up the Golden Staircase, it is hard not to be in awe of the monumental effort that went into trail building, by workers with low-tech tools during an era when heavy equipment was pulled by mule teams.

After you crest Forester Pass, Mount Whitney begins to loom, with its broad, slanting peak dominating the ridge in the distance. It takes about two days from when you first see Mount Whitney to reach its base. Our last night on the trail we camped just below its hulking face near the last lake, which is shaped like, and named for, a guitar.

After hauling your packs up switchbacks that wind across the talus slope, you reach the highest pass on the journey, where you’ll be joined by surprisingly clean day hikers who have climbed up from the other side. You can leave your pack here and enjoy a few blissful kilometers of pack-free hiking as you trek along Mount Whitney’s ridgeline, winding past pinnacles and narrow windows that look down to the eastern desert valley below. Free of your pack, the 3.2-kilometer climb goes quickly. You finally arrive on the sloping, windswept peak, passing an emergency shelter to join the others posing for pictures and peering down in all directions. At 4,420 meters, you’re on top of the lower 48 states.

The descent is steep, quickly dropping from almost barren talus to alpine meadow to forest to high desert steppe in just a few hours. Strolling through the last kilometer of sagebrush makes it hard to believe that you were just on top of the world. You can savor the end of your journey slowly, or dash through, depending on how motivated you are to reach the shower, pizza and beer waiting for you in the town of Lone Pine at the end of your 340-kilometer journey exploring the Sierras.

Be aware and prepare

This is bear country. Food must be stored in bear canisters every night.

Hiking the full 340-kilometer length of the John Muir Trail (JMT) isn’t a beginner backpacking trip. Make sure you enjoy slowly plodding up switchbacks carrying a heavy pack for days before you start out on this weeks-long trek. That said, I met a surprising number of people for whom the JMT was their first wilderness foray, and as far as I know, they all survived.

The hike itself is hard, climbing over nine passes near or above 3,350 meters. Depending how fast you travel, it takes several weeks to a month to hike. We did it in 21 days. (You can hike sections of it in a day or a week as well — however long you have — which many people do.)

The logistics of the trip provide their own challenge, similar to other through-hikes such as the Appalachian Trail or the Pacific Crest Trail, albeit far shorter than both. The Pacific Crest Trail (which runs from Canada to Mexico) actually follows the JMT through this stretch of California. Like on those trails, you must plan ahead and figure out your food situation: how much food you will need to carry versus what you should send ahead in your resupply boxes. You can mail packages with food and extra Band-Aids — or whatever you think you might need — to three outposts along the trail, where workers will pick up your packages from the post office and hold them for you for a fee. Keep in mind that fires aren’t allowed along many parts of the trail, so you shouldn’t plan on making a campfire and cooking your food each night.

Likewise, you’ll need to figure out how far you plan to hike each day (and thus when you’ll reach your resupplies) as well as what gear you’ll need versus what might become an unnecessary burden on your back. The more you know about yourself and your companions as hikers, the better you can plan.

For example, how necessary is that extra guidebook? After several years dreaming about this trip, my hiking companion and I initially thought we needed to bring multiple guidebooks with us, including both plant and geology field guides and a trail guide, so we would know what we were seeing along the way. The first time I put on my nearly 20-kilogram pack, however, that idea went out the window, and we left all the books behind except for Elizabeth Wenk’s excellent trail guide, “John Muir Trail: The essential guide to hiking America’s most famous trail,” which is written with a naturalist’s eye. The trail guide included not just mileage, key landmarks, elevation gain and campsite recommendations, but also information about how the forest ecosystems transition as you head south, why the appearance of the granite suddenly shifts, and the differences between the various species of ground squirrels that will occasionally try to steal bites of your lunch. “Liz,” as we affectionately began to call the guidebook, offers a taste of everything the observant hiker might want to know and was surely worth the weight. For more serious science, check out James Wise’s “Mount Whitney to Yosemite: The Geology of the John Muir Trail.” For topographic maps, the best choice is Tom Harrison’s pack of 12 waterproof, full-color maps that are small enough to keep the one you need in your pocket.

Packing for the JMT is like packing for any other backpacking trip: Your most basic needs include good shoes or boots and socks, a tent, a sleeping bag, warm overnight clothes, a camp stove and other cooking gear, a water purifier, a headlamp and a first-aid kit (check out a good list of things to bring ahead of time, like the one offered here: A bear-proof food canister is required, at least one per person, which adds an extra kilogram or two. These can be rented from the park’s wilderness office for a small fee or purchased for $75 to $300.

Some folks wing it, figuring everything out after hitting the trail. But knowing that we might often be a full day’s hike or more from an exit point inspired us to take the prep work seriously. And even with careful planning, things are bound to go wrong, like afternoon lightning and hail storms that prevent you from climbing up an exposed pass, or your water-filtration system calling it quits on day three.

Although the JMT runs through wilderness upon wilderness, far from roads and cell phone reception, unlike on some other through-hikes, you’ll rarely go more than a few hours without passing other hikers. You can choose your level of solitude, finding secluded spots to camp alone every night or joining a popular spot to make trail friends. We met endurance athletes trying to do the whole trip in five days; a multi-generational family reunion going just 8 kilometers a day for a short section of the trail; an almost-retired couple training to do the entire Pacific Crest Trail; and groups of college kids.

The John Muir trail is many things to many people, but by planning ahead, you can make the trip work for you.

Kate Prengaman
Wednesday, February 26, 2014 - 02:00

Getting there and getting around on the John Muir Trail

Getting to the trail can be a challenge, but one way is the Yosemite Area Regional Transportation System bus, seen here at the Merced train station.


Copyright Ricky Courtney, Creative Commons Attribution-ShareAlike 3.0

The best time to hike the John Muir Trail (JMT) is late summer. To plan your own adventure, start by reading up on the trek at various websites such as the Pacific Crest Trail Association’s JMT trail site ( and in guidebooks. Then, when you know when you want to go, procure your permits. To start in Yosemite, you can apply for permits through their lottery over the winter or get a permit for an alternate trailhead like we did. Or, if you have enough time to be flexible, you can try to get some of the first-come, first-served permits available every day. Most people do the 340-kilometer trip in two to four weeks, depending on their hiking pace and interest in exploring side trips or taking days off.

Getting to the trailheads can be a challenge. Regional airports in Merced and Fresno are a couple of hours’ drive away from Yosemite Valley; bigger airports in San Francisco, Oakland and Sacramento are four to five hours’ drive. If you start at Mount Whitney and head north, your closest major airport is Los Angeles International, which is about four hours’ drive away. Las Vegas is about the same distance; Bakersfield is slightly closer.

If you can’t rope friends into dropping you off and picking you up at your trailheads, there are a few public transportation options, but most are pretty slow. To get to Yosemite, you can take the Greyhound to Merced, and then switch to the Yosemite Area Regional Transportation System (YARTS) to get into the park. A bus line makes daily trips up the east side of the Sierras, which you can take north to Mammoth Lakes and then catch the YARTS back to the Yosemite front country or to Merced. From the Whitney trailhead, known as Whitney Portal, you can hire a private shuttle to the town of Lone Pine, where you’ll find motel rooms, showers, burgers, beer, cell phone reception and the bus line.

It’s tempting to plan ahead and book a hotel room to be waiting for you at the finish line, but it’s also nice to have some flexibility in your schedule, in case you find yourself moving at a slower pace or need to take a day off for some reason. Many hikers make a vague plan for their return to civilization, but refrain from making specific reservations so they have some wiggle room on the trail.

Kate Prengaman
Wednesday, February 26, 2014 - 02:00
Kate Prengaman

Prengaman ( is a natural resources reporter in Washington.

Wednesday, March 5, 2014 - 02:00