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.

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

Beneath unsuspecting visitors feet, a capsule containing pieces of America’s civil rights history.

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

A replica of the famous memorial statue at the Normandy American Cemetery hides in an office building in downtown D.C.

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

This unassuming passageway played a key role in one of the most important events in U.S. history.

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

Over the last century, this elegant columned facade has been home to the headquarters of a bank, several nightclubs, and a restaurant.

During the Industrial Revolution this “Temple of Invention” was full of intricate miniature machines and gadgets.

Go take a picture with the inventor of the daguerreotype photographic process.

Before founding the American Red Cross, Clara Barton had a tremendous humanitarian impact by locating thousands of missing soldiers.

The story behind this beloved toy—named for Theodore Roosevelt and owned by his grandson—is more complicated than you might guess.

An atomic bomb-proof strongbox protects the U.S. Constitution from terrorists and thieves.

This fallen red oak tree has been transformed into a piece of trailside art.

This museum offers a journey back to the Belle Epoque era of Romania.

This once-derelict building is now one of the most beautiful bookstores in the world.

This memorial to the victims of the Romanian Revolution of 1989 is often compared to a potato on a skewer.

The bust of Romania’s most notorious ruler, Vlad Dracula aka "Vlad the Impaler," keeps watch over the ruins of his medieval court.

An abandoned pasta factory in the centre of Bucharest, once home to Bulgarian revolutionaries and a hub of crime.

This maintained cabin is where Josie Morris, an occasional associate of Butch Cassidy, lived out the last 50 years of her life by herself.

This innocent-looking townhome is actually a subway exit.

During the holidays, a vintage subway train whisks New Yorkers back in time.