Parks in Washington, D.C.

A secret greenspace hides atop a Capitol parking garage.

Part of a WWII submarine is lurking outside the Washington Navy Yard parking lot.

A clone of a cloned tree that was so important it allegedly had its own guards.

Cold War intelligence agents monitored communist embassies from an attic in a former pigeon coop.

There's a crumbling old mansion inside the Smithsonian National Zoo.

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

The national park was once a plantation estate.

People escaping slavery may have hidden inside a corpse vault.

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

This lovely pocket park is one of the most under appreciated 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 only tennis court that falls under the jurisdiction of the central bank.

A derelict bit of transportation infrastructure hidden in the woods.

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

Four bald cypress trees in Lafayette Square, across from the White House, mark the southern edge of a 100,000 year old cypress swamp.

A small triangle of DC grass is the final resting place of one of Sonny and Cher's songs.