Fittingly, America's museum of architecture is itself a magnificently designed old building.

The hippo that stands on this university campus was once a drunken flea market purchase.

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

An unkempt, oddly placed piece of land keeps an elderly farming couple in a residential area.

The last of Fairfax County's one-room schoolhouses.

Bohemian paradise covered in majestic forests.

Collecting 700 years of mechanical death-dealing, the NRA's sprawling gun museum is a revealing testament to the American obsession with armament.

At 207 feet, one of the world's longest continuous escalators.

The local community brought back this land to transform it into a nature preserve.

The Lincoln Memorial has inspired many, even though a word on the inscription appears to be spelled incorrectly.

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

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

Once home to the largest photo service in the United States.

This nine-story building is the oldest standing skyscraper in D.C.

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

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

The winding route passes through an enclosed alleyway, two tunnels, and leads to the White House basement.

After James Madison's death, his wife and former First Lady Dolley Madison lived in this yellow building near the White House.

Before Nixon, "watergate" meant canals.

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

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.

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

This lonely waterfront memorial to the men of the Titanic was erected by the "Women of America."

The grand marble structure next to the White House is Andrew Carnegie's temple to Pan-American diplomacy.