Visit Hopkin's Chocolate Cave

Go to the Lava Beds National Monument Visitor Center.  Pick up a caving permit.  This cave is located on cave loop road which is a loop road with multiple caves past the visitor center.  You will need a flashlight, good shoes or boots, and water.  In this cave you will experience many interesting cave features including bacteria that makes the walls and ceilings look different colors, there is a section with cracks in the ceiling, and very cool looking passages.  If you have never been caving and seen the geology of the underworld it is a great experience.