The world's oldest continuously operating airport was founded by the Wright Brothers.

A relic of FDR's brief foray into utopian urban planning.

The tunnel under the Capitol Building where Congress takes out its trash.

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

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

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

The National Park Service’s best-kept secret with views that rival any in D.C.

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

The monument's pointy aluminum tip has been melted down by repeated lightning strikes.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

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

On the Fourth of July this area will transform into a Pompeii-like storm of falling embers and ash.

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

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

The most accurate timepiece in the world.

The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.

The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

The hidden offices underneath Memorial Bridge have been locked up since 1976.

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

The romance of early commercial flight still fills this Art Deco destination.

This lovely picnic spot featuring thunderous jet landings is an aircraft spotter’s dream.

The national park was once a plantation estate.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.