Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

Alexander Hamilton’s creation caused quite a bit of controversy.

This elaborate towering structure was once famed for its revolutionary height.

A mine fire has been burning under the deserted town since 1962, but this church is still going strong.

A toxic ghost town sitting atop a massive coal fire.

The trials and tribulations of marking Poe's grave.

The United States Capitol's former columns still stand.

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

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

The walls of the iconic dome are hollow and have a secret stairway.

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

This restaurant has been a haven for D.C.'s LGBTQ community since the 1950s.

An atomic bomb-proof strongbox protects the U.S. Constitution from terrorists and thieves.

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

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

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

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

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

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

An overlooked memorial honoring the local Washington residents who died in World War I.

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

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

The only place for a truly presidential dram.

One of the best places to see feral Colonial Spanish Mustangs in the United States.