An obscure waterfall that looks like something out of a fantasy novel.

A wall of chewing gum moonlights as collective art.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

This rustic old building is said to be the most photographed barn in America.

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.

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

Disks are rolled out onto the south lawn to absorb the impact of Marine One's wheels like giant coffee coasters.

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

Corn-inthian columns with a uniquely American take on neoclassical architecture.

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.

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

One of the most influential presidents in U.S. history wanted only this plain, elegant monument as his lasting memorial.

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

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

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

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

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

Perhaps the most scandalous statue of America's first president.

A three-story tower of books about Abraham Lincoln is one of the more unusual monuments to the president.

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

The national park was once a plantation estate.

Rumor has it the uncarved lump behind the three famous suffragists is reserved for the first woman president.