The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

Every day a troupe of pampered water fowl walk the red carpet to their favorite fountain.

Home to drunken tower-climbing goats... seriously.

The 10th-tallest pyramid in the world, this former sports arena is now home to a massive Bass Pro Shops store.

Yup, that's where the name came from.

What was once a presidential estate is now an exotic menagerie and home to the Budweiser Clydesdales.

400 million-year old limestone caverns nestled in the Ozarks served as shelter and a hideout for cultures throughout North American history.

This futuristically sylvan church is a glass-enclosed marvel of modern architecture.

This restaurant serves wood-fired fare served in a natural cave with a live spring.

This mountaintop refuge rehabilitates tigers, lions, bears, and more from illicit wildlife trade—and offers overnight lodging.

Mobsters came for a soak in the hot springs, and stayed for the illegal gambling and bootlegging.

This Arkansas town is known for its gangster history, its healing waters, and now its brews.

Two gushing waterfalls of hot spring water within a block of each other.

Over thousands of years, this slot canyon was carved out of the bed of an ancient lake.

This replica of an 8th century burial ship actually sailed to Norway before returning home to Minnesota.

"...I guess that was your accomplice in the wood chipper?"

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

Hidden behind Lincoln's head is a chamber containing enamel plates documenting American history, sealed in a teakwood box in a titanium vault.

One of the largest collections of wildlife art in the United States, built into the side of a cliff in rural Wyoming.

This rustic old building is said to be the most photographed barn in America.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

A beautiful geyser under environmental threat.

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