The first memorial dedicated solely to the Black troops who fought for the Union.

A gorgeous mural outside a beloved D.C. restaurant pays homage to famous Black Americans.

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

This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

Sit where JFK proposed to Jackie or where Nixon dined on meatloaf at this storied pub.

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

The preamble to the U.S. Constitution written entirely from vanity license plates hangs in the Smithsonian museum.

This forgotten boat elevator was an engineering marvel in its heyday.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

A heroic pigeon that, through a barrage of gunfire, delivered a message that saved over 100 lives in World War I.

A much-maligned monument to teetotalism.

This sandwich shop has a century-old elevator behind a sheet of plexiglass.

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

You could be standing at the site of one of D.C.'s most fatal tragedies and not even know it.

The national park was once a plantation estate.

The most decorated dog of World War I is preserved in the Smithsonian.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

This former shopping outlet is now adorned with beautiful graffiti and murals.

Mysterious hillside with a continuously burning natural fire.

18m long sarcophagus of a constantly growing dead prophet.

This "tower of death" has acted as an observatory, a religious hub, and an executioner's lair.

Light still pours into the ruins of this ancient Islamic observatory.

The Avenue of Mausolea is a series of grand palatial tombs.

A refurbished locomotive from a bygone era in the middle of the Jordanian desert.