This giant boulder is sandwiched between apartment complexes in upper Manhattan.

This abandoned ironworks was once the most important military supplier in America.

An abandoned, rusty old relic of railroad history stands at attention over the Cuyahoga River.

This spectacular public market has got meat, fish, vegetables, baked goods, and enough kielbasa for a lifetime.

Funded by John D. Rockefeller, this is one of the earliest, and most beautiful, shopping arcades in America.

An unoccupied lighthouse encased in layers of ice from the waters of Lake Erie.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

The remains of what was once the world's steepest passenger funicular.

This ancient market is often referred to as the oldest shopping mall in the world.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Stroll through a wonderland of stupendous moss-covered trees.

Elvis's own personal tropical hideaway.

This unique architectural wonder is also tied to one of the 20th-century's most renowned writers.

Just a man taking his prehistoric pet for a stroll.

Mysterious 500-year-old tapestries depict a unicorn hunt.

A room in New York City that contains 250 cubic yards of dirt.

Ride the subways of yesteryear.

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

A maritime museum holding the remains of Blackbeard's pirate ship.

This campus museum commemorates a national tragedy.

Ancient Egyptian wigs, South American feather headdresses, a bounty of anthropological artifacts in Oxford.

Smack in the midst of coal country, this collection provides a peoples' history of Appalachian miners' heritage.

France's most famous cemetery, with some of its most curious tombs.

This 17th-century structure is a beautiful testimony to traditional Persian architecture