See SOPHI perform live at the 8th Annual Austin BatFest on the Cogress Avenue Bridge. The Congress Avenue Bridge in Austin, TX spans Town Lake in downtown Austin and is home to the largest urban bat colony in North America. The colony is estimated at 2 million Mexican free-tail bats. Each night from mid-March to November, the bats emerge from under the bridge at dusk to blanket the sky as they head out to forage for food. BatFest is an event that has become one of the most spectacular and unusual tourist attractions in Texas. See the bats, live music and lots of arts and crafts. Fun for the whole family!