This replica of the Greek structure is in the heart of Nashville.

400 million-year old limestone caverns nestled in the Ozarks served as shelter and a hideout for cultures throughout North American history.

See massive fossils that are over 200 million years old in northeastern Arizona.

A mysterious light floating in the trees of Arkansas may be a piezoelectric effect.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

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

Official museum, hall of fame, and repository of the Texas Rangers.

Housed in a century-old building, this museum's dedicated not just to soft drinks, but to the free enterprise system.

A modernist landscape of water and sci-fi concrete.

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