From there visit the Lava Cast Forest. You’ll have to take a nine-mile dirt road to reach the one-mile, self guided “living museum of volcanic landscapes,” but it’s worth the effort.
It was a little on the warm side on the day we visited the Lava River Cave - a welcome respite. The cave is a constant 42 degrees and it was weird seeing our breath in the middle of August! You can rent lanterns if you don’t bring a flashlight, but you will need your driver’s license and a deposit.