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

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.

Once on display alongside a giant Gumby, it’s as tall as a nine-story building when fully extended.

The "lovely red Vega" of the legendary record-settling pilot.

There's a crumbling old mansion inside the Smithsonian National Zoo.

A nostalgic bibliographic gem.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

There's a 12-foot-tall replica of the Washington Monument hidden under a manhole nearby.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

Home to items never before seen by the public.

Yo, Adrian!

This elaborate towering structure was once famed for its revolutionary height.

Instruments, apparatus, and rare books all relating to chemistry and its related sciences.

The humble field where the first Major League Baseball game was played.

Contrary to popular belief, this secluded statue doesn't represent Pennsylvania's founder.

Golden and naked, the figure that was once the highest point in New York is all that remains of the second Madison Square Garden.

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

An Irish Memorial commemorating those who perished due to potato blight.

A daily replay of the experiment that proved the rotation of the Earth.