The Pentagon is so large that it was planned like a city, complete with internal highway infrastructure.

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

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

At Washington's Dulles Airport is a satellite museum (no pun intended) with three quarters of a million square feet of aircraft history.

A former major munitions plant that has been converted into a sprawling art space.

The only recreation of William Shakespeare's indoor playhouse.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

An eccentric company offers eccentric millionaires the opportunity to have spaceflight-related experiences.

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

At 207 feet, one of the world's longest continuous escalators.

The highest point in Virginia can only be reached by passing through ponies and flowers.

The fanciest public restroom in New York City boasts fresh flowers, art, and a classical music soundtrack.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

A hands-on traveling collection of the innovative devices of yesteryear.

The bank that helped fund the Mexican-American War and the purchase of Alaska met its downfall after helping Augusto Pinochet launder money.

This historic boathouse was constructed using salvaged lumber from burned barns.

Outside the Department of Transportation, a collection of artifacts honors the history of how we get around.

Once a sewer culvert, this road tunnel now offers cyclists and pedestrians a subterranean stroll under the C&O Canal.

The word "Watergate" will forever be associated with the infamous scandal in 1972, but this fountain is famous in its own right.

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

A portal into the bricked up canal that runs through the heart of Washington D.C.

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

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