The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

Nonprofit art center that promotes outsider, intuitive, and self-taught art.

The highest point in Tennessee, Clingmans Dome bears witness to the ravages of one type of insect.

Bizarre lunar-like landscape with thousands of large stone "hoodoos."

There's a 12-foot-tall replica of the Washington Monument hidden under a manhole nearby.

A Swedenborgian glass church surrounded by redwoods sits perched atop a massive landslide area.

A sculpture made of 10 Cadillacs as a monument to the "Golden Age" of the American automobile.

Less a museum than a bizarre fantasy world created by artists and engineers.

The "Seinfeld" diner.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

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

The magic's in the hole!

Scores of vintage street lamps shine along L.A.’s Miracle Mile.

These delicate buggers are some of the rarest fossils that have bubbled up from the Tar Pits.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

A giant bronze coil of feces is both a tribute to doggie defecation and a reminder to pick it up.

An underground mansion with fruit-bearing trees and grapes growing beneath the surface of central California.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

Giant Redwood-themed cafeteria operates under the golden rule, "Dine Free Unless Delighted."