Did You Know Mammoth Lakes Has Volcanoes!?

Oct 20, 2020

The small mountain town of Mammoth Lakes is a geological paradise. Set within the scenic Sierra Nevada Mountains, the community is surrounded by an incredibly diverse collection of volcanoes found along the rim of the ancient Long Valley Caldera. When this super volcano erupted 750,000 years ago, it greatly altered the surrounding landscape and sent volcanic ash as far away as Kansas. Since then, smaller volcanic events have created many of the landforms we know today, such as the legendary playground Mammoth Mountain and the pumice-covered slopes of Mono Craters north of town.

The breathtaking Eastern Sierra offers endless exploration and adventure and regardless of where you go, an opportunity to explore this natural wonderland is always around the corner. From taking a scenic gondola ride to the craggy peak of Mammoth Mountain to guided paddling tours of volcanic islands inundated with migrating birds, Mammoth Lakes has a volcano-based adventure for you.

The Classic Volcano

Mammoth Mountain is one of California’s most famous volcanoes. From its gondola-accessed promontory at over 11,000 feet in elevation, this geologically-young mountain hovers above the town of Mammoth Lakes and provides visitors with unparalleled outdoor recreation throughout the year.  Formed by a series of violent eruptions that spanned from 110,000 to 55,000 years ago, Mammoth Mountain records a time of geologic unrest in the Eastern Sierra. Each of the many individual eruptions left layers of volcanic rock called ryholite and dacite, with distinctly-colored intervals of rock representing separate events.  

While the volcano itself is no longer considered active today, the mountain is still alive with evidence of an explosive past.  Fumaroles discharge steam and volcanic gases from the flanks of Mammoth Mountain and on the southwest side in the Mammoth Lakes Basin, releases of carbon dioxide have killed the forests around Horseshoe Lake.

Getting There

Take California State Route 203 west (north) 5 miles from downtown Mammoth Lakes toward Mammoth Mountain Main Lodge. Or hop on the free shuttle bus from The Village at Mammoth to Mammoth Mountain Main Lodge.

Things to do

  • Ride the scenic gondola to the summit of Mammoth Mountain
  • Explore the Eleven53 Interpretive Center at the top of the gondola
  • Chat with a U.S. Forest Service scientists while enjoying the unforgettable view from the summit
  • Ski in the winter
  • Mountain bike at the Mammoth Bike Park in the summer
  • Hike into the Mammoth Lakes Basin after riding the gondola to the summit in the summer


  • Free parking
  • Restaurants on-site
  • Restrooms with running water
  • Best views in the Eastern Sierra

Get more information about Mammoth Mountain here. 


Easily Accessible, Yet Out of the Ordinary

Obsidian Dome is one of the most unique geologic features of the Eastern Sierra.  From looking at preserved remnants of trees, geologists have determined that this young volcanic feature formed around 700 years ago, or at the beginning of the Renaissance Period, when steam-driven volcanic explosions created a conduit for silica-rich magma to reach the surface. Once this rapidly cooled, the otherworldly Obsidian Dome was formed.

What makes Obsidian Dome so unique is its composition of almost exclusively obsidian, which means the mountain is comprised entirely of volcanic glass!  Because of this, the volcano was very important to indigenous peoples, who collected and traded the obsidian for use in tools, weaponry, and jewelry.  Today, Obsidian Dome stands almost 400 feet above the surrounding forest floor and is barren of vegetation, making this moon-like landscape a great place for every member of the family to explore.

Getting There

From Mammoth Lakes, take California State Route 203 east (south) 1.5 miles to the intersection of Route 395. Travel 10 miles north on 395. Then, turn left onto the gravel Glass Flow/Obsidian Dome Road and follow that road for 2.5 miles. 

Things to do

  • Explore, climb, and hike around the unique Obsidian Dome
  • Venture down a nearby trail into the Owens River Headwater Wilderness
  • Go off-roading on nearby OHV trails
  • Fish for brook trout in Glass Creek


  • Free parking
  • Picnic areas

Get more information about Obsidian Dome here.


For the Adventurous

Mono Lake has a very interesting geologic history that began over one million years ago.  This ancient lake is currently volcanically active, with the most recent series of eruptions occurring within the past 350 years.  These eruptions partially formed the massive Paoha Island in the center of Mono Lake’s hypersaline waters and today, the island remains one of western North America’s most crucial migrating bird habitats.

There is no better way to explore the natural beauty of Mono Lake and Paoha Island than by kayak tour.  Caldera Kayaks offers fully guided tours of Mono Lake along with boat and gear rental packages. The lead guide also works for the U.S. Geological Survey and is able to share his incredible knowledge of the area with guests.

Getting There

From Mammoth Lakes, take California State Route 203 east (south) 1.5 miles to the intersection of Route 395. Travel 20 miles north on 395 to the small hamlet of Lee Vining on the unforgettable shores of Mono Lake.

Things to do

  • Go kayaking or canoeing on the lake
  • Spot native birds and other wildlife
  • Capture photos of the unique landscape
  • Take a free tour from the Mono Basin Scenic Area Visitor Center led U.S. Forest Service Ranger 


  • Free parking
  • Picnic areas
  • Restrooms with running water
  • Restaurants nearby

Get more information about Mono Lake and Paoha Island here.

Jason Abplanalp

Jason Abplanalp first discovered the Eastern Sierra lifestyle six years ago and after brief tenures in Colorado and Idaho, Jason returned to the mountain town he truly loves, Mammoth Lakes, CA. As an avid skier, mountain biker, hiker, and fisherman, Jason believes there is no better place for his family to call home. Jason has…

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