I swam inside of a crater filled with water. It was warm water and I liked that a lot but what I did not care for was wearing a life jacket because free swimming is not allowed. Every single person has to wear a life jacket.
I learned that the water was around 90 or maybe 95 degrees and it is naturally there, not filled up by people. The water gets heated by the earth’s insides, where a lot of heat is trapped. The walls and ceiling are made by minerals building up a little bit at a time for a very long time. I think it was 10,000 years. There is a hole in the top and I could see the sky. About 25 years ago or so, people used to get into the crater through the top! But now there’s a tunnel to go through the side.
I got mixed up in my mind about this at first. I thought that all craters were created by meteors and that’s just not true!