Lassen Volcanic National Park

Conservation area in northern California. Lassen National Park lies within Lassen National Forest (area 4,500 sq km/1,737 sq mi) and occupes a site 64 km/40 mi east-northeast of Red Bluff that covers 431 sq mi/166 sq mi. The park is known for its numerous volcanoes.

The park contains Lassen Peak and the ‘Cinder Cone’ (2,105 m/6,907 ft), a mound of lava surrounded by multicoloured cinders; both were declared national monuments in 1907. There are many dangerous thermal areas, where only a thin crust of cooled lava has formed over steam chambers below. Famous examples of this are the ‘Sulfur Works’, in the park's southwestern corner, and ‘Bumpass Hell’, named after a well-known local guide from the 1860s. In the northwest lie the pinkish lava plugs of Chaos Crags, where a volcano once collapsed. Manzanita and Butte lakes, Eagle Peak (2,811 m/9,222 ft), and the Lassen Volcanic Wilderness are also in the park, which is traversed by the Pacific Crest Trail.