In the middle of downtown Brooklyn lies a 165 year old secret hidden right below the surface (closed to the public indefinitely).

The Battle of Atlanta in 360 degrees, featuring a corpse that bears a striking resemblance to Clark Gable.

Who needs fancy modern water slides when this giant North Carolina rock works just as well?

This Transylvania County city is home to a rare white squirrel population that is descended from an escaped carnival animal.

These eerie outliers of the lightning bug family glow a mysterious blue color.

An unfinished rail tunnel that has since been used to house cheese and bats.

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

The home of aviation trailblazers, in a remote corner of the big city.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

In its day this historic fort held 100 cannons pointed in almost every direction to protect New York.

Lie in a hammock where George Washington stood.

The crown jewel of the Queens Museum is a nearly 10,000-square-foot architectural model of the city originally built for the 1964 World's Fair.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

A hacienda that features all things uniquely Yucatán.

Michael Jackson got Bad and Crocodile Dundee walked on heads in this iconic Brooklyn subway station.

Ride the subways of yesteryear.

One kilometer of thick brass rod laid out before your eyes.

A room in New York City that contains 250 cubic yards of dirt worth a million dollars.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

San Francisco's newly reopened hands-on science museum.

One part local history, 99 parts gruesome haunted house.

A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

In this cobwebbed old operating theater, you can practically hear the screams of the unanesthetized patients.

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