A surprising, but overlooked example of geology in the middle of the nation’s capital.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

Also known as the Founding Church of Scientology.

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

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

This unassuming passageway played a key role in one of the most important events in U.S. history.

The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

Before Nixon, "watergate" meant canals.

Look closely and you’ll notice that the color changes a third of the way up the tower.

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

A building shaped like the Army Corps of Engineers logo, because why not?

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

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

Go take a picture with the inventor of the daguerreotype photographic process.

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

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

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

Senators used to relax in the nearly forgotten marble tubs now hidden in the U.S. Capitol Building's basement.

For 60 years, the academy had no permanent location until members voted Washington D.C. as its forever home.

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

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

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

A traveling postal dog covered 48 states and more than 140,000 miles, and he lives on as taxidermy, patched up with a rabbit's foot and a pig's ear.

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