Cold Boiling Lake

Overview

Cold Boiling Lake is a quirky little stop where cold water looks like it’s boiling—thanks to carbon dioxide bubbling up through the lakebed. It’s a “dying” hydrothermal feature, so expect gentle fizzing near the shore rather than dramatic churn. Still, it’s a neat, low-effort way to see Lassen’s volcanic plumbing at work.

Getting There & The Hike

The easiest approach starts at Kings Creek Picnic Area. From there it’s about 0.8 miles one way (roughly 1.5 miles round-trip) with a brief uphill early on, then mostly gentle terrain. Expect occasional muddy patches near the bubbling spots. Snow can linger into summer; early season, some routes may be marked across snow.

What You’ll See

Look for small bubbles along the shoreline and in adjacent seeps—many visitors report the action is subtle and limited to small areas, and sometimes not visible at all. The surrounding meadows can host wildflowers mid to late summer, and you might spot deer or mountain birds. Some stretches of nearby trails pass through Dixie Fire burn areas, which adds stark contrast but less shade.

Extend Your Hike

• Crumbaugh Lake: Continue past Cold Boiling Lake to reach this pretty lake at about 1.3 miles from the trailhead.
• Bumpass Hell: From Cold Boiling Lake, it’s another 1.9 miles up to the east end of Bumpass Hell (about 2.6 miles one way from Kings Creek). That segment can be steeper, rocky, and includes a tricky creek crossing—hiking poles help. This route is known for wildflowers and views.
• Mill Creek Falls to Kohm Yah-mah-nee: Beyond Crumbaugh Lake, drop to Mill Creek Falls (about 3.0 miles from the trailhead) and continue to the Kohm Yah-mah-nee Visitor Center (about 4.6 miles). Stock is not recommended on the Bumpass Hell segment.

Practicalities & Safety

Stay on marked trails—hydrothermal ground can be unstable. Don’t enter the water; gas can displace oxygen right at the surface. Pets aren’t allowed on park trails. Parking at Kings Creek is first-come, first-served and fills on busy days. There are no facilities at the lake; reliable restrooms and water are available at Kohm Yah-mah-nee Visitor Center (southwest entrance) and additional restrooms at Loomis Plaza (northwest). Cell service is spotty around Kings Creek. Standard park entry fees apply.

Best Time to Visit

Typically late June through October, depending on snow. Bumpass Hell often opens mid-July. Summer mornings are your best bet for easier parking and cooler temps; afternoon thunderstorms are possible. Mosquitoes can be active near meadows and lakes in early summer—pack repellent.