Lassen Volcanic National Park

Lassen Volcanic National Park sits at the southern terminus of the Cascade volcanic arc, which stretches from northern California through Oregon and Washington. The park is unique among national parks because it contains all four types of volcanoes: shield volcanoes like Prospect Peak, cinder cones like Cinder Cone, composite volcanoes like Brokeoff Volcano, and the plug dome Lassen Peak. Brokeoff Volcano, roughly 600,000 years old, was once a massive stratovolcano comparable to Mount Shasta, but it has since eroded, leaving only its remnant peaks. Lassen Peak, a plug dome formed roughly 27,000 years ago as a dacite lava dome on the flanks of the older Brokeoff Volcano, is the largest plug dome volcano in the world. Its 1914-1917 eruption series was the most recent volcanic eruption in the Cascade Range until the 1980 eruption of Mount St. Helens. The park's geothermal features result from groundwater heated by molten rock at depth, surfacing as fumaroles, mud pots, and hot springs. Bumpass Hell, the park's largest hydrothermal area, features a boiling pool named Big Boiler that reaches 240 degrees.

The Lassen Peak Trail is a 5-mile round trip climb gaining 2,000 feet to the summit of Lassen Peak, offering panoramic views of the Cascade Range, including Mount Shasta to the north. The trail is typically snow-free from July through October. The Bumpass Hell Trail is a 3-mile round trip boardwalk through the park's largest hydrothermal area, passing boiling mud pots, steaming fumaroles, and turquoise pools. The Cinder Cone Trail, in the remote northeast section of the park, is a 4-mile round trip to the rim of a 700-foot cinder cone with views of the Fantastic Lava Beds and Painted Dunes. The Manzanita Lake Trail is an easy 1.6-mile loop around a scenic lake with views of Lassen Peak reflected in the water, and the Lake Helen Trail offers a short but steep hike to an alpine lake at 8,200 feet. The Kings Creek Falls Trail descends 2.3 miles to a 50-foot waterfall. The park also offers backcountry camping with permits and has over 150 miles of trails through diverse volcanic terrain.

Lassen Volcanic National Park is located in northern California, roughly 50 miles east of Redding, the nearest city with full services. The park is accessed via Highway 89, which runs north-south through the park, and Highway 44, which approaches from the north. The 30-mile park highway is typically open from late May through October, with winter closures due to snow. Entrance fees are $30 per vehicle, valid for seven days. The Kohm Yah-mah-nee Visitor Center, at the southwest entrance, is open year-round and offers exhibits, a cafe, and bookstore. The Loomis Museum, at the northwest entrance, is open seasonally from late May through September. The park has seven campgrounds, including Manzanita Lake Campground with reservations through Recreation.gov and several first-come, first-served campgrounds. There is no lodging inside the park, but the nearby towns of Mineral and Shingletown offer limited services, with Redding providing a broader range. The nearest airport is Redding Municipal, with Sacramento International roughly 165 miles to the south.

Lassen Volcanic National Park has a short summer season due to its high elevation, with the park highway typically opening in late May or June and closing by October or November due to snow. Summer, from July through September, is the best time to visit, when trails are snow-free and wildflowers bloom in the meadows, particularly in July. Fall offers cooler temperatures and aspen color in the lower elevations, typically in October. Winter is the longest season at Lassen, with snow depths often exceeding 20 feet at the higher elevations. The park highway is closed, but the southwest area remains accessible for snowshoeing and cross-country skiing, with ranger-led snowshoe walks offered on weekends. Spring is a transition period, with snow lingering well into May and June. Even in summer, nighttime temperatures can drop below freezing at high elevations, and afternoon thunderstorms are possible. The park's high elevation means that visitors should be prepared for rapid weather changes, and hiking to Lassen Peak should not be attempted during thunderstorm conditions due to the exposed summit.