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

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

A priceless collection of the Nation's cryptologic history.

This fort down the Potomac from Washington, D.C. was once the only defensive fort protecting the capital.

The longest escalator in the Western Hemisphere takes over three minutes to ride down.

This rare triple-jurisdiction drawbridge passes through Virginia, Maryland, and Washington, D.C.

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

A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

A lovely aquatic park built by a one-armed Civil War veteran who made a fortune from lotuses.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

The sci-fi villain is a little-known inhabitant of the U.S. capital's largest cathedral.

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

The site of the climactic scene from the classic horror film is now a historic landmark.

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

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

Right next to departures—how convenient!

Rumor has it the hot dog stand was targeted by two Russian nuclear missiles.

One of the dwarven trees dates back to 1625 and survived the Hiroshima bombing.

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

The United States Capitol's former columns still stand.

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

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

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

Art deco landmark on the outskirts of Washington, D.C.