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

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

Seemingly grown on some other world, these New Mexico rock formations look like a disused science fiction set.

One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

Internationally recognized group that works to protect the wolf and educate the public about its plight.

Low tide reveals 8,000-year-old rock carvings in Southern Alaska.

Gorgeous cave resemble a winter wonderland.

One believer transformed a local curiosity into proof of Vikings on the Great Plains.

The largest land animal skull ever discovered.

A peculiar forest that was handcrafted for government experiments.

American bison herd descending directly from a Bronx Zoo breeding program that saved the species from extinction.

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

This little slice of old Jerusalem in Oklahoma is the evolution of a 90 year old passion play.

Final resting place of Geronimo, Quanah Parker, and the first atomic gun ever fired.

"They died with their boots on."

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

This unique tower has been home to malaria-fighting bats for 100 years.

The summer home of the largest colony of bats in the world.

Abandoned railroad tunnel is home to a colony of three million Mexican free-tail bats.

This former Texas landfill is flush with 300 million-year-old fossils, all fit for the taking.

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

Belly up to the bar in Cowtown, don't forget to buy some boots.

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

A Victorian mansion, painstakingly reproduced to appear just as the the Munster's family home did on TV.