Lassen Volcanic National Park, CA | Pigsah National Forest, NC | Bob Marshall Wilderness Complex, MT | Dome Land Wilderness, CA | Mahoosuc Mountains, ME | Algonquin Provincial Park, Ontario | Owyhee Uplands, ID/OR
Swap out: Yellowstone National Park
Swap in: Lassen Volcanic National Park, CA
Geology isn’t measured by the eon at Lassen; it’s a current event. Fumaroles hiss, mudpots burp, and backcountry lakes bubble. A hint of rotten-egg hydrogen sulfide occasionally wafts on the breeze. The mountain itself is a temperamental toddler, formed 27,000 years ago–yesterday, in geologic terms–and it erupted as recently as 1915. Earth’s violent process of tectonic recycling is on display here (mostly for the exclusive benefit of backpackers) as at no other park in the Lower 48 but one: Yellowstone. At both parks, a plume of molten rock from deep within the planet sits perilously close to the surface. Periodic eruptions mark the landscape, making Lassen a showroom for the full volcanic product line, including hydrothermal features and examples of four types of volcanoes–plug dome, shield, cinder cone, and composite. Naturally, all this action gets geologists worked up about the place. "It’s very exciting to have all of these volcanoes in such proximity, and have so much recent material to examine," says Dot Loftrom, coauthor of Geology Trails of Northern California.
Backpackers can get worked up over the 150 trail miles, and the fact that the park flies below the tourist radar. "Lassen’s where we go on Memorial Day and other holidays because it’s so uncrowded," says Richard Bothwell, the "chief fun officer" for San Francisco’s Outdoor Adventure Club. "We’ll lead groups to the top of a cinder cone with a panoramic of lava beds and colored dunes, and it blows people away."
That great stringer of scenic beads, the Pacific Crest Trail, slices through the park’s center, from Badger Flat to Little Willow Lake. An 18-mile shuttle trek brings you close to fascinating geothermal features, like the bubbling, highly acidic cauldrons in Devils Kitchen (a highly recommended 4-mile round-trip detour); Boiling Springs Lake, which simmers at 125°F; and Terminal Geyser, a steam vent that warms and odorizes its immediate surroundings. The PCT is relatively flat here, so the miles go easily. Camp in near Twin Lakes, or beside any of the creeks feeding into Corral Meadow.
Call this the firewater tour, heavy on volcanic relics and loaded with lakes. The secluded 30-mile route starts at an unnamed trailhead just inside the park’s southern boundary in the Warner Valley, and ascends steeply from inside an ancient caldera to an elevated plateau. Cruise past Juniper Lake through forests of lodgepole pine to camp on Snag Lake’s north shore, where you can poke around the Fantastic Lava Beds, enormous flows of black basalt that oozed from the base of nearby Cinder Cone in 1650. (The lava dammed a stream, forming Snag Lake.) The next day, scuttle through loose cinder up and over stark Cinder Cone for views of Lassen and other, lesser volcanoes. After rounding Butte Lake, spin off toward Widow Lake into the park’s emptiest quadrant. The trail to Red Cinder Cone, which also eventually leads to a camp beside Jakey Lake, soon becomes faint, demanding routefinding skills. Finish by retracing your steps from the first day around Juniper Lake.
Pair the 1:48,000 Lassen Volcanic National Park map ($9) with Tracy Salcedo’s Hiking Lassen Volcanic National Park ($15).