The boiling mudpots and hissing steam vents at Sulphur Works hydrothermal area are accessible year-round via a two-mile round-trip, over-snow route. Hydrothermal features are visible on both sides of the snow-covered park highway route and heat from these features often keeps the portion of road between them clear of snow. This is the only park hydrothermal area that is accessible in the winter months (approximately November through April). The 30-mile park highway closes to through traffic in the snow season (approximately November through April).
Distance: 2 miles round-trip
Elevation: 6,700 to 7,000 feet
Average Snowshoeing Time: 1 hour
To access Sulphur Works, follow the snow-covered park highway route from the Southwest Area parking area. The route passes the Kohm Yah-mah-nee Visitor Center and a sledding area. The one-mile route climbs gently along a hillside above Sulphur Creek and offers a partial view of Lassen Peak at about the halfway point. The left side of the route is bordered by steep side hills. Be aware of avalanche danger by watching for movement on the steep slopes above. Near the end of the route you will cross Sulphur Works bridge and the summertime Sulphur Works parking area on your left. Rising steam and the scent of rotting eggs makes your destination is unmistakable. From here you can return the way you came, continue 1/2 mile up the highway route to Windy Point, or begin the steep climb to Ridge Lakes. View these and other winter routes in the Southwest Area.
In the winter months, travel by snowshoe or cross-country ski is best for traveling over the deep snowpack. Bring your own equipment; rentals are not available in the park. This popular route may be hardpacked, especially through the sledding area just beyond the visitor center. This route is recommended for advanced cross-country skiers only as footprints and snowshoe tracks on this popular route freeze and make skiing more difficult. The Manzanita Lake Area offers better routes for beginners. We do not recommend walking without snowshoes unless the route is completely hardpacked. Otherwise, you should be prepared for your feet and legs to break through the snow frequently in an exhausting experience known as post-holing. Learn about why not creating postholes is good for everyone from Leave No Trace Center for Outdoor Ethics.
Improve everyone's safety and enjoyment by adhering to the following winter etiquette recommendations:
- Do not walk on ski tracks. Footprints and snowshoe tracks create hazards that make skiing more difficult.
- Snowshoe parallel to the ski track. Using a separate track ensures snowshoers remain clear of downhill skiers.
- Yield to faster skiers or downhill traffic. Step to the side to allow skiers traveling downhill to safely pass. In all other cases, yield to those traveling uphill, as they are working harder and have the right of way.