Building a Dome
Building a Dome The dome-shaped rock that holds Vulcan's Eyeresembles what Lassen Peak—a plug dome volcano—once looked like. Layers of lava from older volcanoes built the mountain to a level near the trailhead parking lot. A vent opened through the layers 27,000 years ago and pasty lava oozed like toothpaste squeezed from a tube. The lava piled up, building the 2,000-foot dome you are climbing today. Submitted by: Eric Goodill