Austin is home to many things: live music, the University of Texas, the state capital; but many people don't realize Austin is also home to the nation's largest urban bat community-and it's right downtown. More than 750,000 Mexican Free-Tail bats make their home under the beams of the Congress Avenue bridge. Following renovations of the iconic bridge in 1980, the bat population took up shelter under the bridge, and it has been their home each summer since.

During the cooler months, the bats make their home in Mexico, but every year during March and April they make their way North to Austin to give birth and feed on the cities abundant bugs (coincidentally, the summer months are when Austin's cricket population reaches its height as well). And before the sun goes down, when they're resting up for their nightly romp around Austin, the bats spend their time under the Congress Avenue bridge. Each evening, just before nightfall, the bats leave their refuge en masse, in an incredible natural exodus-a massive swarm of hundreds of thousands of Mexican Free-Tail bats swirls its way up around the bridge, then dissipates as the bats head off in every direction to feast.

Apparently, the renovations made in 1980 left deep crevices in the bridge, which provide an ideal habitat for the bat colony. Many Austinites consider this an accidental blessing, as the bats are credited with greatly cutting back on the insect population both within the city and throughout the surrounding countryside. In fact, it's estimated that, as a group, the bats consume between 10,000 and 30,000 pounds of insects!

This incredible sight has become an integral part of summer in Austin, and draws hundreds of spectators nightly during the summer months, culminating in late August, when the colony is at its largest-averaging around 1.5 million bats. Austinites have come to treasure and even celebrate this unique natural phenomenon, with a summer celebration called BatFest. Held during the last weekend of August each year, BatFest brings together all of Austin's favorite things-live music, food, people and (you guessed it) the Mexican Free-Tail bats. The family-friendly event features educational displays, arts and crafts, and a whole host of activities centering around the Congress Avenue bridge bats-plus more than 30 bands rocking the weekend away from two different stages.

Austinites love a good reason to party-it's a trait the city is well known for. In fact, BatFast falls just a few weeks before Austin's biggest music festival, Austin City Limits, which draws thousands of visitors a year and brings the country's hottest bands to Austin, Texas, for one sweltering weekend each September. But, unlike ACL or South by Southwest-Austin's other major music festival, which also doubles as a film festival-BatFest is first and foremost about promoting the protection and appreciation of one of Austin's natural wonders.

In a city with such strong environmental pride, and wonderful resources like Barton Springs Pool and Edwards Aquifer, it's no wonder this incredible phenomenon would capture the imaginations-and hearts-of so many.