The institution is sitting on a goldmine of 21,000 paints, varnishes, pigments, and primers preserved for posterity.

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

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

The towering figures were created from the cemetery's fallen old-growth trees.

An overlooked oasis of quiet on the grounds of Washington's monumental basilica.

A much-maligned monument to teetotalism.

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

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

An easily overlooked memorial to a Ukrainian famine-genocide that killed over 4 million people.

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

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

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

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

A brass plaque dedicated to a convicted cannibal hangs in the National Press Club, and that's not even the craziest part of the story.

In the basement of the U.S. Capitol Building is a hidden storage room full of ornate floor tiles leftover from the 1850s.

Obscure Freemasons still live in D.C.’s largest private residence.

The first presidential bomb shelter was located in an old vault under the Treasury, connected to the White House via tunnel.

A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

This poor little statue is the most vandalized memorial in Washington.

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

These recently uncovered walls are all that's left of Washington, D.C's first defense contractor.

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

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

A hoard of sky catalogs, astrophysical journals, even the works of Galileo and Copernicus.