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

This strange seaside tower got its name from a wealthy eccentric who would hide coins among its stones.

A hand-built folk art installation covered with messages of God's love.

Art school in the Amazon: Drugs, nature and sustainable agriculture.

An unexpected desert oasis in South America.

This scalding hot river was thought to be a myth until one geoscientist made it his quest to study the mystical waters.

A remote candy-striped mountain in the Peruvian Andes straight out of the pages of Dr. Seuss.

Keshwa chaca, among the last handwoven Incan bridges, crosses Apurimac Canyon in Peru.

One of the best places to see feral Colonial Spanish Mustangs in the United States.

North Carolina's finest examples of Native American pictographs have survived for 5,000 years.

Where scientists keep miles of very valuable ice from Antarctica and Greenland from melting.

The childhood home of Henry Jones Jr. is now an adventure-themed bed and breakfast.

An architect in Aspen used psychedelics as his muse while building this mushroom masterpiece.

When ecosystems collide in the arid Southwest.

The highest bridge in America was built for an almost unnervingly small amount of money.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

This naturally-sourced hot spring is now home to a clothing-optional resort.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

This highest peak in Idaho can only be reached by traversing a formation known as "Chicken-Out Ridge."

A black cottonwood gets a second life as a home for books.

Natural rock water slides hidden in the remote forests of northern Idaho.

A legal loophole makes it possible to get away with murder within this 50-square-mile section of Yellowstone.

These black pillars of volcanic basalt seem to call mountain climbers with an unbreakable siren song.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.