Catacombs—Lava Beds National Monument
Location: Tulelake, California
Length of visit: 3 hours
Major draws: Lava tube cave, most challenge cave in the park
Strenuosity: 10 out of 10
Cost/Fees: $15 per vehicle or America the Beautiful pass
Additional considerations: Flashlights necessary, extremely tight passageways require crawling, good map reading skills essential
Description: Complex cave system with multiple layers.  A 2-mile loop route can be completed which requires extensive duck walking and multiple areas of crawling with one-foot high ceilings.  Bump cap and knee pads required past first 800 feet.  Route is very mentally and physically challenging.