Lava Tube

Lava Tube is a conduit where lava once flowed, cooled and created a cave-like hole in the rock above Lower Twin Lake. This geologic formation is commonly referred to as "Hole in the Wall." The Lava Tube is a popular destination for backcountry skiing: skiers begin from from the back side of Mammoth Mountain, an out-of-bounds area, and descend the experts-only slope through the rocky tunnel. Winter visitors are advised to view Lava Tube from the eastern shore of the lake because of avalanche danger. In the summer, you can walk around the lake for a closer look.
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Lava Tube is a conduit where lava once flowed, cooled and created a cave-like hole in the rock above Lower Twin Lake. This geologic formation is commonly referred to as "Hole in the Wall." The Lava Tube is a popular destination for backcountry skiing: skiers begin from from the back side of Mammoth Mountain, an out-of-bounds area, and descend the experts-only slope through the rocky tunnel. Winter visitors are advised to view Lava Tube from the eastern shore of the lake because of avalanche danger. In the summer, you can walk around the lake for a closer look.

Avalanche Forecast for 01/27/2025

AVALANCHE FORECAST: You could trigger an avalanche in areas where winds deposit new snow on all aspects near and above treeline. It will also be possible to trigger sluffs of loose dry snow in steep, unsupported terrain. Light snow covering shallowly buried obstacles remains a hazard, and is worth considering when deciding where and how to travel in the backcountry today. Find out More

Destination Activities
Public Services
Hours of Operation: N/A

Season: Year Round
From the Dragon's Back Access point, take the Dragon's Back Trail to Lava Tube. Note that the trail sign incorrectly reads "Mammoth Mountain Trail."
- Get driving directions to Dragon's Back Access
- Get public-transit options*
*Note that not all facilities are accessible via public transit.