World's first "penitentiary," meant to be humane, drove men insane.

The site of a tragedy in 1908 that claimed the lives of 171 people and changed fire safety laws across the state.

The internal railway of one of the biggest steel plants in America has been transformed into a linear park with unique industrial views.

A former plant in one of the hubs of U.S. steelmaking has been turned into this museum celebrating the history of American industry.

The headquarters of the Fraternitas Rosae Crucis, complete with Rosicrucian pyramids, all in the Pennsylvania woods.

The whole world in one water tank.

A secret rendezvous spot where John S. Mosby and his Rangers would meet to divvy up their loot after raids.

Remnants of a wall built to separate Black residents of Hall's Hill from a newly built subdivision are a grim reminder of segregation in 20th-century Virginia.

Surrounded by traditional homes, this Tolkien-esque dwelling stands out on a quiet street in suburban Maryland.

A whopping 14,000 copper coins cover this miniature fighter jet.

This suburban park recalls the history of a famous tavern. Despite the name, it's no ordinary place!

This monument traces the segregation line that inspired the first rural branch of the NAACP.

Two distinctive homes on a New England village green look like a couple of frosted wedding cakes.

These disused steel furnaces are now haunting ruins that may one day be a national park.

Pittsburgh's literal underground railroad.

This restaurant offers a side of antiques, curios, and a bathroom chock full of owls.

A beautiful oddities shop crammed with strange and morbid curiosities.

This plaque marks a place where one of Hollywood’s most famous dancers got his start.

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

Sections of the iconic limestone columns have been left uncleaned as a reminder of the city's polluted past.

The last remnants of Fort Pitt also hold the distinction of being the oldest structure west of the Allegheny Mountains.

A giant ball made from pieces of an old Jeep.

The only statue of its kind to commemorate Washington's beginnings as an officer of the British Colonial Militia.

An abandoned railroad tunnel transformed into a creepy path for hikers and cyclists.