Into the Caldera: the Bishop Volcanic Tablelands Overnighter

Long Valley, the Volcanic Tablelands, Lake Crowley, Mono Lake, and in general, the graben known as Owens Valley hold timeless stories beneath the silty soil, sage, and rabbitbrush. This area has long intrigued me, looking past its main attractions: Instagram-famous – or infamous – hot springs and world-class fly fishing. The landscape is rugged and steep, with unsuspecting silt traps enveloping your wheels up to the hubs as winds flex their prowess as shape-shifting forces spanning eons. Yet its magnetism, beauty, indigenous, and geologic history make it prime for bikepacking, touring, gravel riding, and road riding. It will take some planning, the right equipment, and some determination.

Before we get rolling, geologist Dillon Osleger shares a brief history of the area. When I reached out to him, requesting a 400-word summary, he said: “An active million years is a lot to fit into 400 words.” At any rate, for those familiar and unfamiliar, this will help wrap your head around how this magnificent area was formed.

Tablelands and the Long Valley Caldera: A Brief Geologic History – Dillon Osleger

There is a calming presence to the expanse of land between Mammoth Lakes, CA and Bishop, CA. Pastel color palettes adorn topography, ecology, and crepuscular skies, giving a soft tone to the landscape that belies a tumultuous past.

From June, Ian Carrico. “The Long Valley Caldera / Bishop Tuff Paroxysm : The Geology of a Supervolcanic Eruption.” (2014)

The scales of geologic processes in this region are vast, in both temporal and spatial senses. The Long Valley Caldera acts as the keystone to this complex region, having collapsed 760,000 years ago in conjunction with an eruption from its southern edge that released 500 times more volcanic material than the 1980 eruption of Mt. St. Helens. The material from this eruption, both gaseous and solid, enveloped the surrounding landscape under a cloud of ash and pyroclastic flows. These currents of volcanic gases and fragments which flowed down the flanks of collapsing structures moved in excess of 100km/h due to their high density relative to the surrounding atmosphere.

Eventually, this material slowed and consolidated into a layer thousands of feet thick known as the Bishop Tuff ignimbrite. This ignimbrite, a geologic formation named after precursory pyroclastic flows (igni – fire, imbri – rain), stretched from the northern end of the Caldera at Mono Craters to modern day Owens Valley. Magma unreleased during the initial eruption resulted in subsequent flows of rhyolitic lava, masking much of this formation in the immediate vicinity of the caldera. However, significant portions of this layer are exposed as a downward sloping plateau to the southeast known as the Tablelands.

Lava flows, alluvium from surrounding mountains, and water from the Owens River filled the Long Valley Caldera until 100,000 years ago, when water levels exceeded the height of the Southern rim and eroded the natural dam to carve out the Owens River Gorge that meanders through the Tablelands today. The flow from the Owens River increased through time as climate fluctuated, reaching a maximum flow around 16,000 years ago as the last of the glacial ice sheets of the Sierra Nevada melted out. The raging torrents of water resulting from a warming climate deepened the gorge and formed the abrupt erosional edge where the Tablelands plateau meets the Owens Valley, just north of Bishop.

Volcanic activity in this region has been dormant for the past 100,000 years, although a significant body of congealed magma still underlies the caldera, providing a source of geothermal heat that feeds hydrothermal systems, namely hot springs, throughout the region. These hot springs, accompanied by the fertile plains and clean water of the Owens River, eventually drew anthropogenic interest. Petroglyphs mark the residence of the Paiute-Shoshone indigenous nations, while dams, aqueducts, and draught-stricken lands attest to the nature of colonization, whereby William Mulholland and the city of Los Angeles plundered a river for the viability of a city in a desert. That story, however, is best told in long form (see Cadillac Desert – Marc Reisner) rather than as a footnote in a summary of geologic history.

On the Importance of Solo Outings

Originally, I wanted to do this trip with friends. Last year, a big group had planned on doing it but the snow came to the region early, coating the entire Tablelands with feet, not inches, of powdery-white snow. We reconvened this year, a bit earlier on the calendar and made tentative plans. Yet, one by one people couldn’t make it. Rather than scrapping the ride, I decided to relish some solo time in one of my favorite parts of California. Sure, it makes for slightly less interesting photos and story but there’s a lot to be said about doing something by yourself, for yourself.

Even though there is familiarity on this ride, I still have a hard time sleeping the night before. The anxiety sets in. All the ‘what ifs?’ trace across my mind. I even woke up at one point thinking I heard someone stealing my bike. The weather forecast wasn’t looking so peachy either. Maybe I should just go on a day ride? Or maybe I should just go home. That’s the curse of the solo outing, you don’t have anyone relying on you but yourself.

There I was, with this brand new bike, built to do exactly this kind of riding. I had to make this happen. We often wax poetic about overcoming struggles through cycling but the biggest tribulation often begins before the cranks even take the first turn…

Reportage: Traversing the Tablelands and Into the Long Valley Caldera

As with much of the ride and bicycle touring reportage present here on the Radavist, it is my intent to bring forth geopolitical, geological, and indigenous histories, as much as an educational vehicle and as a way to show respect to these complex issues. While we addressed part of the hydro-political issues with our Cerro Gordo Reportage, as well as the Indigenous histories in many other pieces, let’s dive right into the experience of traversing the Bishop Tablelands and ascending into the Long Valley Caldera.

This whole region may be a modern-day playground for anglo-Americans with its popularity in the rock climbing, bouldering, fly fishing, and OHV communities but it was once the thriving homeland to the Paiute and Timbisha Shoshone, specifically in the Caldera, the Utu Utu Gwaitu Paiute Tribe, which translates to “Hot Water Place People.”

The “hot water” is perhaps the reason this area has grown in such popularity over the past few years as the Caldera is home to numerous hot springs. Simply search the geotag for Long Valley, Mammoth, or even Bishop and you’ll see rock tubs trapping the Paya, or water into tubs fit for one, two, and up to twenty people. Any ride that can end or intercept a hot spring is worth doing and that may have been one of the main motivations for me to work on this route and tell this story.

Having ridden many of the roads in the tablelands and as someone who spends a lot of time exploring these zones, I was well aware of what I was getting myself into, bracing for the potential for environmental fluctuations of shoulder-season riding in an area on the ecological cusp of the Northern Mojave and Great Basin. These two collide in between the Sierra and White mountains and weather moves quickly from the higher elevations, across the valleys. While the temperatures will be favorable in the fall, expect headwinds, lots of loose silt, and steep doubletrack. A convoluted maze of OHV trails zig-zag their way across escarpments, around ancient trees, and down into dead-end sand traps. Come spring, there might be snow still present yet I would avoid riding this route in the summer months. There’s a window of pleasant riding towards the end and beginning of the calendar year. Plan accordingly.

As such, my bicycle recommendation would err on the side of more rubber. Sure, you can do this with a 40mm tire but there are sections of sand that will not be fun. In good faith, I would say leave the drop bar, go fast bike at home and take something like a rigid mountain bike with at least a 2″ tire. Plus or fat bikes will be sluggish on some of the climbs but will command the descents. 

Navigating the region is easy, as long as you have a paper map and some bearings of where you’re headed. Now, this route is just a sampling of what is available in Long Valley, with a vast network of roads meandering all the way to Mono Lake. I suspect many readers of this website are looking for 2-3 day tours, not necessarily a week-long venture. The region itself also lends itself for excellent gravel riding if hub-and-spoke style rides are more your thing. If you do, however, wish to pack your bicycle with provisions and pedal north into the tablelands, here’s what you need to know.

Water refilling is available in various forms, from natural springs bubbling through the silt, to full-on rivers, hot creeks, and spigots. The thing is, you’ve got to pedal up a 30-mile climb if you wish to begin in the mountain town of Bishop, California. This means strapping 8-10L of water to your bike or doing water drops. Most 4WD/AWD vehicles will make it through these dirt roads just fine, pending for some deep sand spots if you do plan on caching water.

My plan was to pack water, since the weather can turn from pleasant and overcast, to windy and sunny in an instant. I’d rather have enough water and take it slow than constantly be worried about my consumption. You’re exposed, at elevation, and in a very arid place. I can’t stress this enough. For reference, I went through 6 liters on the first day. Hydrate!

Climbing up along Fish Slough Road, you will be greeted with many signs and pull-outs denoting petroglyphs, which are purported to be between 1000 and 8,800 years old. These elaborate designs, which are classified as Great Basin Curvilinear, are carved into the soft ignimbrite rock and were possibly made by the ancestors of the native Paiute-Shoshone. Take your time and if luck is on your side, you can experience these moments by yourself as the wind snakes through the various channels of rock. Rides like this are about being in the moment, so don’t rush past these areas. I like to sit in the sand, let my heart rate rest, and just be there. I know it’s not much but I feel like being in the presence of such work requires being still.

Upon reaching Chidago Canyon, the terrain spikes in elevation and the real climbing begins. Brace yourself for a shift in scale as the canyon walls border the narrow road. This is the Tableland traverse. From here on up, your mind will be distracted by the scale, tonality, and life found within this stunning passage. Expect to see various birds, jackrabbits, lizards, and snakes scurry to the hole of their liking as you slowly climb up and over these peach-colored rocks.

Ascending the tablelands is no small feat and I wish I could say it gets easier. Once topping out around mile 33, you descend into Long Valley with views of Lake Crowley, Owens River, and smaller geothermal creeks. Take your time here, find a hot spring of your liking, and seek seclusion amidst the rabbitbrush and sage. There is plenty of water, just be sure to filter it, and remember, it is frowned upon to camp right next to a hot spring. People do it but that doesn’t mean it’s right.

Up until this point, the riding has been mostly dirt, save for a few miles of pavement. Depending on where you camped, the dirt rollout in the morning is short, before taking on a scenic, 11-mile climb to breakfast at Tom’s Place cafe, one of the smaller establishments on the southern side of Highway 395. Make sure they’ll be open during your trip. Don’t trust Google, give them a call. After a full day of immaculate gravel roads, you might wince at the notion of riding pavement, yet the Sierra backdrop provides plenty of distractions. Keep an eye out for deer, in the early mornings and don’t mind the vehicular traffic, most people are friendly. You’ll get a lot of friendly honks, peace signs, and thumbs up from the locals. If you decide to stop at Tom’s Place, you should fill up your water. Even though the remaining part of the day has a lot of descending, you’re in for a hard afternoon.

Casa Diablo Road, going south, is one of the most beautiful and tough roads I’ve ridden in the area. Navigating the myriad of double track roads to get to it will take up a majority of the day’s time. Once on it, however, expect a ripping descent back down to Bishop, off the shoulder of the tablelands. Without spoiling it too much, be forewarned, there is a lot of sand at the bottom, hence the suggested tire size of 2″.

This route is equal parts beautiful and hard. With the right gear, plenty of water, and a willingness to traverse these sacred lands, you’ll be in for a real treat. If you have comments, or questions, be sure to drop them in the comments! Below is a map with water, petroglyphs, food, springs, and sand marked along the route.