Then there is what was considered Bamberger's folly. In 1998, he decided to carve out a three-dome cave into one of his hillsides and line the ceiling with gunite. The ranch staff rolled their eyes when he told them he wanted enough room for a million Mexican free-tailed bats. For years, no bats came. But slowly, they began to find Bamberger's cave, and now as many as 400,000 bats make their summer home there. The cave is called a "Chiroptorium" — a term his wife and son came up with that combines Chiroptera, the scientific order bats are in, and auditorium.