The Best Places Around the World to See Bats (by the Millions)

The Congress Avenue Bridge in Austin, Texas, is home to the largest urban bat colony in the world. The bridge was reconstructed in 1980, and its crevices made an ideal roosting location for bats, who began flocking to the bridge by the thousands. Residents of Austin reacted negatively at first, but soon realized that the roughly 1.5 million bats provided free pest control for the city, eating 10,000 to 20,000 pounds of insects each night.

Austin's daily newspaper, the Austin-American Statesman, supported the creation of the Statesman Bat Observation Center, on the southeast corner of the bridge, which gives visitors a place to watch the nightly fly-outs. Each year, more than 100,000 people make the trek to Austin to see the bats take off on their evening flights.