Lassen Peak is a volcano. So is the gentle, sloped mountain a few miles away. So is the jagged crater in the park's northeast corner, and so is the broken, ancient massif that used to be even bigger than all three. Between them, Lassen Volcanic National Park holds all four types of volcano found anywhere on Earth, a claim both the National Park Service and the US Geological Survey state plainly and by name.
Shield, Composite, Cinder Cone, Dome
USGS names all four by their park landmark directly: Prospect Peak for the shield volcano, a broad, gently sloped mountain built from repeated fluid basaltic flows; Brokeoff Volcano, the ancient composite volcano whose collapsed remains include Brokeoff Mountain, Mount Diller, and the roadside stops most visitors already pass; Cinder Cone, a steep, symmetrical cone of loose volcanic rock in the park's quieter northeast corner; and Lassen Peak itself, a plug dome, formed when thick lava pushed straight up rather than spreading out.
It's a short list of names, but it's a genuinely rare thing to find grouped this close together. Most volcanic landscapes specialize in one shape. Lassen has all four within a single park boundary, each one a real, physically distinct kind of eruption, not a matter of degree.
Plan Your Lassen Visit
See all four volcano types on one drive up Highway 89, or add Cinder Cone as a separate stop with the trip planner.
Open the Trip PlannerLassen Peak's Real Superlative
Lassen Peak, the plug dome that gives the park its skyline, tops out at 10,457 feet and formed roughly 27,000 years ago when thick, slow-moving lava pushed upward instead of flowing out, piling into the steep-sided dome that stands there today. The National Park Service states plainly that it's the world's largest dome of its kind, a title stated by elevation and formation, not by a volume figure NPS doesn't publish.
- Shield PROSPECT PEAK
- Composite BROKEOFF VOLCANO
- Cinder cone CINDER CONE
- Plug dome LASSEN PEAK, 10,457 FT, WORLD'S LARGEST
Facts checked against the National Park Service's own Lassen volcanoes page and its article on volcanic domes, plus the US Geological Survey's Lassen Volcanic Center page, which independently confirms all four volcano types and names the same four park landmarks.
Four kinds of volcano, four different ways for the earth to push rock upward, all visible from roads and trails most visitors already walk. Lassen doesn't advertise this the way it might. It's simply true, stated plainly by two federal agencies, and visible from wherever you happen to be standing in the park.