This forgotten boat elevator was an engineering marvel in its heyday.

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

A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

A clone of a cloned tree that was so important it allegedly had its own guards.

When it opened during the final years of the embargo, all the drinks and cigars were free.

This poor little statue is the most vandalized memorial in Washington.

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

There’s a hidden military meme engraved on the World War II Memorial.

You could be standing at the site of one of D.C.'s most fatal tragedies and not even know it.

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

There's a crumbling old mansion inside the Smithsonian National Zoo.

This sandwich shop has a century-old elevator behind a sheet of plexiglass.

A historic ruin just 20 feet away from a busy highway onramp.

The "lovely red Vega" of the legendary record-settling pilot.

Rumor has it the uncarved lump behind the three famous suffragists is reserved for the first woman president.

The most decorated dog of World War I is preserved in the Smithsonian.

D.C. once had its own tiny rival to the New York Stock Exchange.

A line of blue paint marks the route of the inaugural parade.

A painfully obvious spy house sits right across the street from the Russian Embassy.

During the Industrial Revolution this “Temple of Invention” was full of intricate miniature machines and gadgets.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

A promising candidate for the lost rock laid by George Washington was unearthed, but the hunt is still on.