This statue of two men in a rowboat was erected to honor those who died while fishing in the Chesapeake Bay.

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

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.

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

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

A super-sized promotional trick that is now a D.C. landmark.

Largest Roman Catholic church in North America.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

Government testing at the asylum briefly explored using marijuana as a "truth serum" on Nazi prisoners of war.

The oldest continuously operating fish market in the United States.

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

A historic neighborhood church is reborn as a psychedelic arts collective.

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

A girls' boarding school inspired by the Chicago World's Fair, once abandoned, now restored to strange and scenic glory.