Lie in a hammock where George Washington stood.

This small New York museum examines Chinese history from its origins right up to its arrival in the city.

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

This hidden oasis features a stunning view of the Hudson River and the Palisades from a castle-like museum.

Little Red Lighthouse under the George Washington Bridge.

Beautiful mosaics cover the first stations opened on New York City's newest subway line.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

One of only two commuter aerial tramways in the United States.

The iconic D.C. restaurant where the Cuban Missile Crisis was negotiated, now a Walgreens.

It was once the base for a series of domestic terror attacks.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

The grand marble structure next to the White House is Andrew Carnegie's temple to Pan-American diplomacy.

Also known as the Founding Church of Scientology.

One critic described it as "middle Mussolini, early Ramses, and late Neiman-Marcus." Another called it an architectural "natural disaster."

An ear-piercing buzzer calls lawmakers to a vote with a series of long and short rings to form coded messages.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

When it comes to handsignals (and colonialism) rock always beats scissors.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

Home to a vast and influential collection of Shakespeareana.

The most accurate timepiece in the world.

Decades before the scandal, this staircase on the river was a literal "water gate."