An immense cave that has served as an outlaw's treasure trove, an underground dance hall, a nuclear fallout shelter, and much more.

Civil War dumping ground for the bodies of terrorized Union sympathizers.

Constructed in 1859 as a general store and post office, the store is still used to this day and was featured in the Walking Dead series.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

Austin’s local mountain isn’t really a mountain at all.

An enormous pink granite batholith, long attributed with spiritual powers by the Tonkawa Indians.

These sub-farmland caves are home to a majestic stalactite known as the "Crystal King."

A popular swimming hole that hides one of America's most deadly diving spots.

Hike the ruins of a zoo that was shut down by an unsolved murder.

In Houston's airport, a cow is properly equipped to jump over the moon.

The only airport with a people mover system designed by Walt Disney Imagineering.