There are spots in it where there are no lights. Devil's staircase is one. There are bats on one side of the cave but we were not allowed to go there when I went and m not sure why.
All lights were on when I visited
Currently there are no guided tours. So all lights are on all the time. There are no bats, trolls or other demonic creatures in the cave. Though do take a sweater with you it's 50 inside, due to the devil's breath
Bats live basically in most caves. Yes. They do turn the lights off, but i seen no bats. It was awesome! Totally do it!
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