Type
Historic Site
Location
40.5348°N 121.4907°W
Hot Rock is a roughly 30-ton boulder at the foot of the Devastated Area along the Lassen park highway. A 1915 lahar carried it down from Lassen Peak, and visitors reported it was too hot to touch for months afterward.
Details
- Type
- Historic Site
- Accessibility
- Limited accessibility
Overview
The boulder, weighing about 30 tons, was carried down the slopes of Lassen Peak during a 1915 lahar in a slurry of mud, earth, and rock. Visitors to the altered landscape reported that it stayed hot to the touch for months after the eruption. Photographer Benjamin Franklin Loomis documented the 1915 to 1916 eruptions and made a well-known image of Hot Rock. The boulder rests at the bottom of the Devastated Area, alongside the park highway.