A memorial for an outsider theorist who believed that the planet is actually hollow.

An unusual, super-sized grocery adventure awaits in an Ohio suburb.

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

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

Railroad officials in the early 1900s sought to spare travelers the sight of Roman soldiers’ private parts.

An easily overlooked memorial to a Ukrainian famine-genocide that killed over 4 million people.

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

After his presidency, George Washington planned to live only a few blocks from the Capitol building.

The tunnel under the Capitol Building where Congress takes out its trash.

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.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

"Congress may voluntarily remain in session throughout the summer, in order that our Congressmen may be protected from the intolerable discomforts and dangers of the ordinary outdoor weather!”

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

A street in front of NASA's D.C. headquarters has been named in honor of the Black women who were essential to early spaceflight.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

The oldest continuously operating fish market in the United States.

A tribute to the pop culture icon overlooks this Washington D.C. intersection.

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

Light bulbs, scrap wood, and tinfoil comprise this homemade throne of the gods.

The first purpose-built art gallery in the United States is once again open as a center of craft arts.

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

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

Decades before the scandal, this staircase on the river was a literal "water gate."

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