"Austin Bats Sail from Congress Avenue Bridge" Pastel, 12" x 8" Image Size Austin Texas has the largest urban bat colony in North America, and it is estimated they number close to 1.5 million Mexican free-tail bats. They live under the Congress Avenue Bridge in downtown Austin. I painted this from a photo we took from Ladybird Lake (then Lake Austin), just at sunset when the bats come out and fly overhead. Sold - Prints Available