Few years ago few people decide to go inside cave and they never come back, police found them dead. I was there yesterday , be careful.
No it's free
It does not cost to go to the cave but you can not get inside the one at the Piasa Bird. It is fenced off due to rocks falling on people. There is a trail over by the fence though that leads back to caves that aren't blocked off.
The cave is not open to the public. There are ways to get in, i.e. openings in the fence, but I don't really recommend going in, as you could possibly get in trouble for trespassing. So basically enter at your own risk.
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