This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

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

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

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

The hidden offices underneath Memorial Bridge have been locked up since 1976.

During Prohibition, the U.S. Congress had an "official" bootlegger, with his own Capitol Hill office.

A sculptor's dream castle turned fantastical ruin.

Herbert Hoover's "Brown House" rural presidential retreat was a PR disaster amid the start of the Great Depression.

An overgrown garden stands as a grim marker of an unrealized dream.

The Virginia home of one of the signers of the Declaration of Independence is being preserved with a unique glass facade.

Under a playground is a little-known sealed train tunnel that likely contains the bodies of workers trapped by cave-ins.

A home built with marble tombstones from the graves of 2,200 Union soldiers buried in a Virginia cemetery.

An innovative attempt to break a siege in the American Civil War still scars the earth today.

The eerie ruins of a remote abandoned hamlet said to be founded by the survivors of a shipwreck.

The flower-shaped temple in Virginia aims to transcend the boundaries of the world’s religions.

An intricately designed junk art house with four extravagant junk art cars hidden in the suburbs.

The beautiful tunnel that ran from the lobby to Penn Station is still hidden underneath 34th Street.

One of the oldest anatomical theaters in the U.S. still in use was once the site of an infamous cadaver riot.

A train station that was abandoned by the coal industry and was later converted into a cocktail bar.

This demolished goliath of American industry once loomed over the depressed town it once made thrive.

This historic iron-working village is now a ghost town so immaculate that it looks as though it was recently built.

In the woods of New Jersey lie the ruins of a munitions village abandoned after World War I and the remnants of a 1920s wooden racetrack.

The rusting remains are visible sticking out of the waters of the Delaware Bay.

This beautiful stone arch bridge wasn't even expected to stand for one day, but people have been crossing it for centuries.