Lassen Volcanic National Park

Lassen Peak erupted in a series of blasts a century ago, throwing ash across the region and leaving a devastated area that is still recovering, and the park around it is unusual for containing all four principal types of volcano within one boundary: shield, composite, cinder cone and the plug dome of Lassen Peak itself. The hydrothermal areas are the draw, with Bumpass Hell a boardwalk through boiling mudpots, fumaroles and milky sulphurous pools that smell accordingly, and Sulphur Works right beside the road. A trail climbs Lassen Peak in a few hours. Because it sits in a quiet corner of California with a road that is buried by snow for much of the year, it gets a small fraction of Yosemite's crowds.

What you'll find

• Bumpass Hell - the boardwalk through boiling mudpots and fumaroles.
• Lassen Peak - the plug dome, climbed on a switchback trail.
• The Devastated Area - the ground still recovering from the eruptions.
• Cinder Cone - the near-perfect cinder cone with painted dunes beyond.

When to go

July to October is the practical season; the park highway is closed by snow from roughly November until June or even July, and Bumpass Hell often stays snowbound into midsummer. Autumn is clear and quiet. Check road and trail opening before travelling, as the season is genuinely short.

What to expect

The main road is buried in snow for over half the year, which limits the park to a short summer window and catches out many would-be visitors. Hydrothermal ground is thin and lethally hot beneath, so the boardwalks are not decorative. The sulphur smell at Bumpass Hell is strong. Lassen Peak's trail is exposed and hot in the afternoon.

Nearby

Redding is an hour and a half west; Mount Shasta rises to the north.

Key facts