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

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

A beautiful geyser under environmental threat.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

The rocks in this arid basin leave trails of movement behind them.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

Most-visited and most-photographed slot canyon in the American Southwest.

A parade of antique steeds offers a quirky ride through history.

Thousands of American timepieces on display in the former clock-making capital of the country.

New Preston and Kent, Connecticut - where Friday the 13th, Part 2 was filmed.

Eclectic collections, artwork, and some feline friends fill the writer's former home.

A historic 1890s architectural masterpiece with an iconic clock tower that, once open to the public, now faces an uncertain future.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

This curved Manhattan building was built to house the opulence of John D. Rockefeller's oil empire.

A well-worn marker in a forgotten alleyway is all that remains of what had been one of Manhattan's most beautiful buildings.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

The oldest operational cathedral in the U.S. has one shell of a way of projecting speakers' voices.

The South's nickname was supposedly born at a former bank in New Orleans' French Quarter.

The only rotating bar in New Orleans has been slowly spinning since 1949.

By day this New Orleans square is for pedestrians, but by night it is a kingdom of kittens.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

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

Revolutionary War casualties fill the only 17th century structure remaining in Manhattan.