Lassen Volcanic National Park
Distance: 3 miles Time: 1.5 hours Type: There are back
Bumpass hell is the largest hydrothermal area in Lassen - think of it as a mini Yellowstone. Here you can find some active evidence of Lassen's volcanic character, where the water temperatures can reach near boiling point. The area is named after a cowboy from the 1860s, who laid a mining claim, but unfortunately fell into one of the mudpots and had to have his leg amputated. Make sure you don't suffer the same fate and stick to the boardwalks!
This hike is fairly short and easy. It takes you from the trailhead between Emerald Lake and Helen Lake, and can be found a short drive from the southern entrance to the park. If you don't want to turn around and retrace your steps you can make this a longer hike by continuing to Cold Boiling Lake and Kings Cross Picnic Area, or turning south to Conard Meadows - but you'll need to arrange for transportation to pick you up at either location.
Most of the walk is on a boardwalk, and the trail meanders up and down until it eventually reaches the geothermal zone. It can get popular and is suitable for families and children.
Unlike Yellowstone, Lassen doesn't have any geysers so don't come expecting dramatic eruptions of water. You'll see some bubbling water, steam and mud - and a lot of pretty clay and rock. You'll also smell sulphur, which always helps to bring the geothermal experience to life alive.
For more information on day hikes in Lassen: