NSS Convention ~ July 25-30, 2021

Lassen Volcanic National Park

Quick Read:

Although it's not exactly next door to Weed, California, this national park is a must-see if you're interested in volcanoes. Don't expect caves - there aren't any of significance here - but these mountains are still growing and they're doing it right in front of you. Here you can see roaring fumaroles, thumping mud pots, boiling pools, and steaming ground.

If you fly into Reno, this park is on your way to the convention. Bring a camera & plan an extra day to explore this amazing geology!

Bumpass Hell

Out of One Beautiful Form into Another

Lassen Volcanic National Park is home to steaming fumaroles, meadows freckled with wildflowers, clear mountain lakes, and numerous volcanoes. Jagged peaks tell the story of its eruptive past while hot water continues to shape the land.

Established in 1916, Lassen Volcanic is the fifteenth national park created by congress, making it one of the oldest in the nation. Covering over 160 square miles, this park offers opportunities to discover the wonder and mysteries of volcanoes and hydrothermal geology for visitors willing to explore the undiscovered. Some of the features here include boardwalk hikes alongside bubbling pits of mud and hissing cracks in the earth. As steam rises from boiling pools, the smell of sulfur fills the air. While the lava cave areas to the north have cooled over the centuries, Lassen Volcanic National Park is still very much active.

At Lassen snow arrives early and stays late. Jagged features are made smooth by deep blankets of snow, yet far below the surface, a fire still burns. Eroded volcanic remnants, U-shaped valleys, and roaring steam vents illustrate Earth's endless cycle of creation and destruction. Woven into this dramatic landscape are timeless stories of survival, renewal, and discovery.

Here, summer is a time of awakening - lakes thaw, wildflowers bloom in emerald meadows, and the bustle of life returns as forests shed their winter mantle. Once a summer home and hunting ground for the Atsugwei, Yana, Yahi, and Maidu, Kohm Yah-mah-nee or snow mountain (Lassen Peak) is still sacred land.

Bumpass Hell

Bumpass Hell is the largest hydrothermal area in the park and marks the principal area of upflow of steam and discharge from the Lassen hydrothermal system.

Powerful Forces

Lassen Volcanic National Park illustrates Earth's powerful forces. Every rock originated from volcanoes, and all four types - shield, composite, cinder cone, and plug dome - can be found here.

Lassen Peak is one of the largest plug dome volcanoes in the world. Its last eruptions were between 1914 and 1921, with the largest explosion on May 22, 1915. The eruptions, photographed by local businessman Benjamin F. Loomis, paved the way for the creation of Lassen Volcanic National Park on August 9, 1916. Scientists continue to monitor the landscape. No one can say when or where the next eruption will occur, only that it will.

A Living Landscape

Boiling mudpots, steaming ground, roaring fumaroles, sulfurous gases... Rain and snow feed the hydrothermal system that lies deep underground. Heated by molten rock, this water rises to the surface creating the remarkable features found in the park. These features are evidence of active volcanism and indicate the potential for future eruptions.

Lassen Peak Eruption

View of Lassen Peak in eruption seen from Manzanita Chute. Benjamin F. Loomis Historical Photograph Collection, NPS.

Click here to download a geologic field-trip guide to Lassen Volcanic National Park.

Lassen lies at the crossroads of three biological provinces: the Cascade Range to the north, the Sierra Nevada mountains to the south, and the Great Basin desert to the east. This convergence contributes to the diversity of ecosystems and the abundance of flora and fauna found in the park. Over 745 distinct species have been identified.

Scientists are studying ecosystem shifts influenced by climate change. Concerns include species and habitat management, changes in precipitation, snow pack, and wildfires.

Life in this rugged landscape is intrinsically untamable and dependent on the balance of natural systems, which, in turn, affect those living beyond the wilderness. Melting snow replenishes four watersheds, providing clean water downstream, while forested mountain slopes help clean the air. Lassen's fragile ecosystems and their diversity of life provide opportunities for education and scientific research, while the night sky, nearly unaffected by light pollution, glows with constellations, meteor showers, and the Milky Way. The majority of Lassen is managed as designated wilderness, a retreat from civilization.

Roadside hydrothermal

Today's Weather: Lassen Volcanic National Park, CA

  • Updated: Saturday, June 12 at 6:16 am
  • Reporting Station: LASSEN LODGE (LSNC1)
  • Elevation: 4,159 ft.
  • GPS: 40.344144;-121.713733
  • Data provided by: National Weather Service
54° F

Regional Map Forecast Wind: none
Humidity: 66%
Dewpoint: 43°F
Barometer: N/A
Visibility: N/A

Today: Sunny, with a high near 75. South southwest wind 3 to 10 mph.
Tonight: Mostly clear, with a low around 44. South wind 3 to 9 mph.