The iconic D.C. restaurant where the Cuban Missile Crisis was negotiated, now a Walgreens.

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

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

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

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

Disks are rolled out onto the south lawn to absorb the impact of Marine One's wheels like giant coffee coasters.

An ear-piercing buzzer calls lawmakers to a vote with a series of long and short rings to form coded messages.

The U.S. Navy’s preposterously detailed mini battleship took 77,000 hours to complete.

‘Bush the old fire dog died of poison July 5th, 1869. RIP.’

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

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

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

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

The unique traffic pattern named for an influential urban planner is also known as the Pedestrian Scramble.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

This lovely pocket park is one of the most under appreciated in D.C.

A historic arena where the Beatles played their first concert in the U.S.

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

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

The national park was once a plantation estate.

The span is crooked and made from two older recycled bridges.

Every drop of D.C. tap water flows through this old waterworks.

Was there a small "backpack nuke" hidden in the attic? JFK apparently thought so.

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