Summary:
Explore the heart of the Park’s geothermal activity, with a close look at mud pots, steam vents and boiling springs.

The popular trail to the main thermal area of the National Park climbs steadily 500 ft/150 m through pine trees, with views over the surrounding hills. From the high point, it is a descent of 250 ft/75 m into the aptly named Bumpass Hell.

Boardwalks lead through an eerie landscape of yellow, sulphur-stained rocks, plumes of steam, bubbling mud pots and hot springs. Be sure to stay on the trail in this area – the ground is thin and scalding water is close to the surface.

This is not a loop trail so you will need to retrace your steps to return to the parking area.

Miles of trails give further options if you wish to explore the variety of scenery in the National Park. Other trails along Lassen Park Road include:

* Summit Lake Loop. A full day, 9 mile/15 km trail that loops through forest and past many of the lakes in the central area of the Park. Heading east from Summit Lake, the trail climbs 500 ft in the first mile to a junction that signals the start of the loop. Keep right and descend a total of 500 ft to reach firstly Echo Lake, and then Upper Twin and Lower Twin Lakes. Keep left at the trail junctions to loop back via the Cluster Lakes. Trailhead: east side of Summit Lake, accessed by a trail from the North or South campgrounds, which are almost midway between the NW and SW entrances.

* Terrace-Shadow-Cliff Lakes Trail. Descends 350 ft to Terrace Lake and Shadow Lake (ignore the side trail on the left early on). A further descent of 300 ft, and a spur trail to the right, leads to Cliff Lake. Total distance of this out and back trail is 3 miles/5 km. Trailhead: turnout 21 miles from NW entrance, 8 miles from SW entrance.

* Lassen Peak. A steep climb to the volcano’s 10,457-ft summit, where you can view lava flows from the 1915 eruption and a panorama stretching to Mount Shasta on a clear day. 5 miles out and back, total ascent of 1,994 ft/608 m. Trailhead: parking area 22 miles from NW entrance, 7 miles from SW entrance.

* Mill Creek Falls. 4.5 mile/7 km out and back trail leads through forest to the highest waterfall in the National Park. Undulating nature of trail means total climbing there and back of about 600 ft/180 m. Trailhead: Southwest campground, close to SW entrance station.

* Brokeoff Mountain. First part of the trail follows a stream as it climbs steadily 2,600 ft/790 m to the 9,235-ft summit. Out and back hike totals 7.5 miles/12 km. Trailhead: turnout 0.25 mile south of SW entrance.

Directions: Hwy 89 (Lassen Park Road) runs through the western half of the National Park, from the north-west (NW) to the south-west (SW) entrances. From I-5, take Hwy 44 east to connect with the 89 and the NW entrance. The SW entrance is reached via I-5 and Hwy 36 east.

Trailhead: Parking area 6 miles from the SW entrance, 23 miles from the NW entrance.

Length: 3 miles / 4.8 km

Trail Type: Out and back

Elevation Change: 500 ft / 152 m
Total ascent of 750 ft/230 m.

Duration: 2 hours

Trail Condition: Easy to follow. Boardwalks in the thermal area.

Features: Geothermal activity.

Climate: Hiking usually only possible June to October, as heavy snow in winter closes Lassen Park Road. Some trails accessible in winter with snowshoes.

Accommodation: Five campgrounds along Lassen Park Road, available on a first-come, first-served basis. Outside SW entrance – motels and cabins at Mineral and Mill Creek, 9 miles west and 9 miles east respectively on Hwy 36. Outside NW entrance – B&B and cabins at Shingletown, 19 miles west on Hwy 44, and north on Hwy 89 at Old Station and Hat Creek.

Trail Notes: Be aware of altitude and possible snow on trails. Thin ground in thermal area makes wandering off trail potentially dangerous. Hiking maps available at both ends of Lassen Park Road – Loomis Museum visitor center at Manzanita Lake and the Southwest Information Station.