This massive subterranean fissure is known as the "underground Grand Canyon."

These beautiful ruins deep in the Pennsylvania woods are thought to have been a ski lodge or a speakeasy, but no one really knows.

An allegedly cursed tree represents a town's reckoning with a racist past.

A historic grist mill and active sluice on the Black River.

The largest collection of Frazetta originals in the world.

A park full of outsider art, created by college students studying outsider art.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

America's first serial killer rests in anonymity.

This semi-spooky remnant of an abandoned hotel provides fantastic views.

An unusual and eclectic collection of local historical memorabilia.

This salt lake in South Australia features seasonal color changes and its very own loch monster.

The drama of nature in full effect in this Nevada State Park.

This massive geographical sculpture is so subtle, it's possible to pass by it without noticing.

Hidden amid a collection of trails is the site of a tragic crash.

This collection of odd proofs of concept is like taking a walk through the imagination of a Victorian engineer.

It's where the final scene of the beloved Tom Hanks movie was filmed.

A collection of sculptures and trails that appear to change with the seasons.

Designed as a labyrinth, this subterranean prison was crafted without bars or doors.

This Elizabethan hedge maze is one of only six in North America.

Live data is transmitted from the Atlantic coast to instantly recreate the ocean waves in this fountain at the NOAA headquarters.

You'll need cowboy boots to trek to this old-fashioned saloon nestled in a giant natural cave.

The Magical World of George Phar Legler.

A wealth of local folk art, antiques, and curios, without ever leaving your car.

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