The largest urban bat population in North America can be found in Austin, Texas, and nowhere is better to see them than at the Congress Avenue Bridge. The bridge’s 6-lanes and pedestrian walkway across the Colorado River take a back seat to the real attraction: 1.5 million Mexican free-tailed bats that make their home under the bridge each summer.

The best place to see the bats at Congress Avenue Bridge is on the grassy hill outside the Statesman Bat Observation Center or on a boat at Lady Bird Lake. The bats begin waking up around sunset and by last light you can hundreds or thousands of bats flapping around, getting their night started.