Washington's iconic carousel has a nice piece of Civil Rights history.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

Look closely and you’ll notice that the color changes a third of the way up the tower.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

The national park was once a plantation estate.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

The site of the climactic scene from the classic horror film is now a historic landmark.

Home to items never before seen by the public.

This is one really big nut.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

This massive mall has hundreds of shops, an amusement park, and a history of deadly amusement attractions.

This 19th century granite fortification is one of the most well preserved forts in New England.

The only sea in the world that has no land boundary.

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

Few other hotels can rival the grandeur of the Castle in the Rockies.

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

The world's longest known cave system.

See massive fossils that are over 200 million years old in northeastern Arizona.

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.

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

I-95's Tijuana-style celebration of kitsch at the Carolina border.

The granddaddy of all tourist traps, built on ice water, jackalopes, and a giant dinosaur.