The Homestead Crater is a geothermal spring, hidden within a 55-foot tall limestone dome. The hole at the dome lets in fresh air and sunlight while the mineral water maintains a constant temperature of 90-96 degrees Fahrenheit. The Crater is the only warm scuba diving destination in the continental US, but you don't even have to get wet to have a one-of-a-kind experience. Many guests come to enjoy the self-guided tour, history, and geology of this amazing, natural phenomenon.