One critic described it as "middle Mussolini, early Ramses, and late Neiman-Marcus." Another called it an architectural "natural disaster."

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

Behind an abandoned storefront is an example of pioneering 1930s gas station architecture.

On the Fourth of July this area will transform into a Pompeii-like storm of falling embers and ash.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

D.C. once had its own tiny rival to the New York Stock Exchange.

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

A line of blue paint marks the route of the inaugural parade.

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

A portal into the bricked up canal that runs through the heart of Washington D.C.

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

When it comes to handsignals (and colonialism) rock always beats scissors.

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

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

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

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

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

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

A tiny monument to the unsuccessful attempt by Thomas Jefferson to place the prime meridian in Washington.

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

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

There’s a hidden military meme engraved on the World War II Memorial.

A haunting tribute to pioneering photographer Clover Adams.

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.