Ha Long Bay's "Cave of Surprises" houses a popular phallic rock formation.

These crumbling towers are some of the last remnants of a centuries-old Vietnamese culture.

Artifacts and memories from the Vietnam war, located in a place that experienced it first hand.

A nightmare for the claustrophobic lies hidden in Southeast Asia.

Hoax, mistake, or evidence of dinosaurs in human times?

An inspired museum dedicated to the patron saint of enslaved people, inside the cloisters where he lived and died.

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

Designed by Buckminster Fuller, this relic of the 67 Expo survived fire and ice.

This massive redwood tree has a hole in the base big enough to drive through.

Every equinox this Maya pyramid puts on a spooky ancient light show.

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

A wall of chewing gum moonlights as collective art.

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

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

A museum and shop on Bourbon Street located in the former home of the second Voodoo Queen of New Orleans.

Quite simply the largest tree in the world (by volume).

This historic "City of the Dead" lies prominently in the center of New Orleans' famous Garden District.

One part antique store, one part curiosities hodge-podge.

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

A museum dedicated to the alleged Roswell Incident.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

This unique structure in suburban Austin is made up entirely of other people's castaways, and constantly changing.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

A battle between nature and architecture in the Cambodian jungle.