A museum dedicated to the alleged Roswell Incident.

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

A spring-fed pool so deep it's used for scuba diving as well as swimming.

Visitors can walk over the largest concentration of Columbian mammoths to have died from one event.

Amazingly detailed marble cinerary urns that once held the cremains of Roman elite.

A high-octane shrine to the greatest Texans who ever lived.

The upstairs reading room is packed with millions of rare books, literary manuscripts, and historical treasures.

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

Modern technology and live displays tell the story of the Pacific during WWII for the Internet generation.

Two massive and unstable sinkholes are yearning to unite, and their consummation could be catastrophic.

Nestled in the heart of a Texas town is a dreamy secret garden dating back to the 1940s.

A registered historic landmark shrouded in unsettling local legends.

Foragers once flocked to this big beautiful bayou to hunt for pearls.

This historical air terminal in Houston is slowly becoming an aviation museum dedicated to the city's aeronautical history.

A view-altering observatory at the University of Texas.

This small town Texas cemetery is said to be the burial site of a UFO pilot who crashed in the 1800s.

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

A Texas cave network is home to some of the world's most spectacular-looking and bizarrely named mineral formations.

It specializes in outsider art and artifacts of secret societies.

The Grand Canyon of Texas.

This sacred cavern, 400 feet deep, is home to millions of bats and an ancient burial ground.

An abandoned quicksilver mining town surrounded by the Big Bend parks.

Mysterious glowing orbs float through the desert night.

Fantastic collection celebrating the final send-off.