"Bat Exodus in Austin If you haven't before seen 1.5 million bats flying out for their nightly feeding at once, now's your chance. The largest urban bat colony in North America, Austin 's Congress Avenue Bridge is the home to hundreds of thousands of Mexican free-tail bats from mid-March to mid-October. Every night around sunset, the colony emerges like a black cloud from the crevices underneath the bridge, heading out to feed on millions of bugs around Austin. A beloved tourist attraction since the bats made their home in the bridge during the 1980 renovations, crowds pack the east-facing sidewalk and the park to the south side of the river to watch the nightly exodus. Want more details? Call the Bat Hotline at 416-5700, extension 3636, for exact exodus times. Christian Bale may or may not answer."