The cave was opened for visiting by tourists only 15 years ago, the tour costs 500 baht, however in my opinion it’s quite overpriced. You will be accompanied by a Thai guide all the time who will light up different stones in the darkness and tell the fairy tales about what animals they look like. Inside the cave you will traveling by canoe first, and then on a bamboo raft, and the biggest part of the journey you will just walk with the water’s level over your knees. So I recommend to wear shorts and suitable shoes.