A painfully obvious spy house sits right across the street from the Russian Embassy.

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

A wondrous old library overlooking the nation's capital.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

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

This grand gothic brewery has been pumping out suds for over a hundred years.

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

A historic neighborhood church is reborn as a psychedelic arts collective.

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

The United States Capitol's former columns still stand.

Home to items never before seen by the public.

Gothic tower mentioned in Thomas Hardy poem "The Channel Firing."

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

Trash escaped from a landfill to fill beaches with all kinds of treasure.

This tiny patch of arid sand sits in one of the greenest states in the United States.

When the town wouldn't allow the fast-food behemoth to build a new restaurant, they put one inside an 1850 home.

An unusually designed bridge from the 1920s was built to withstand the tides and winds of Maine.

Explore the dark underground corridors of this graffiti-covered former military fortification.

The world's third-largest scale model of the planets.

The world's largest model of our planetary system.

An enormous, inside-out glass globe built in 1935.

A historic bridge with a lovely acoustic anomaly.

These impressively detailed battle scenes depict the violence and tragedy of war in miniature.

This giant roadside goose has been hailing travelers into a small Ontario town for over 50 years.