Bracken Cave is the summer home of the world's largest bat colony. With millions of Mexican free-tailed bats living in the cave from March thru October, Bracken holds one of the largest concentration of mammals on earth.

The emergence of these millions of bats, as they spiral out of the cave at dusk for their nightly insect hunt, is an unforgettable sight.

The cave and 697 acres of the surrounding Texas Hill Country is owned and protected by Bat Conservation International. The cave is on the suburban fringe of San Antonio, in an area of rapid population growth. If not for the generous donations of BCI's members and friends, the cave and its remarkable bats likely would have been engulfed by subdivisions.