Lassen is way, way off the beaten path. It's way up in northern California and you could fly into Reno or Tahoe and then drive about 3 hours to get there. Lassen is a volcanic park with the world's largest lava dome.
A lava dome seeps lava that hardens into a dome. Lassen's one of the only places IN THE WORLD where you can see all 4 types of volcanoes ((plug dome, shield, cinder cone, and strato). There's also fumaroles, bubbling mud and hot springs and the uber cool Cold Boiling Lake.
Bumpass Hell in Lassen
Bubbling Mud Pot
“Smell that stinky sulphur in this volcanic wonderland.”