MAY
Texas: World's Biggest Bat Colony

If bats freak you out, it's probably a good idea to give central Texas, and most notably the Texas Hill Country outside Fredericksburg, a wide berth between May and mid-October. Mexican free-tailed bats gather in unnerving numbers—we're talking around 100 million—to feed on tasty Texan insects and raise their young in the area's many caves. The region's Bracken Cave alone has nearly 20 million bats—the single largest colony in the world. Just after sunset, these little suckers pour from their caverns, giving out bloodcurdling, um, squeaks. If you prefer to view your bats in a more hip and happening destination, head for Austin: The 1.5 million Mexican free-tailed bats that hang under Congress Bridge are believed to be the world's biggest urban colony. From mid-March to November, huge crowds gather at dusk—probably after a stiff drink at a local bar—to watch thousands of these winged demons take flight.

Where to stay: While Fredericksburg is charming enough, with ample B&B options, you might prefer to bed down at the 98-room Watermark Hotel & Spa in San Antonio, 60 miles away, if you're averse to chintz and frilly pillows.

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