North America's oldest quarantine facility was built in response to Philadelphia's 1793 yellow fever outbreak.

Surrounded by industrial sprawl, a small monument marks the site of William Penn's first landing in Pennsylvania.

The only geyser in the state of Pennsylvania is caused by pressure from an abandoned coal mine outside of the ghost town Centralia.

A toxic ghost town sitting atop a massive coal fire.

A mine fire has been burning under the deserted town since 1962, but this church is still going strong.

Pennsylvanian mass grave and possibly mass murder.

An occult-y, historic hotel with the World's Largest Ouija board on the roof.

Penn State's giant bug collection.

A model of a dinosaur that was named for Andrew Carnegie stands outside the museum that also bears his name.

A daily replay of the experiment that proved the rotation of the Earth.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

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

This lush Florida island is home to the ruins of a crooked ship breaker's tiny empire.

This historic collection of Native Alaskan artifacts was resurrected through a partnership between the WPA and tribal artisans.

A modern ghost town whose inhabitants were driven away by the growth of nuclear power.

This jail which was in service for over a century is now open for curious visitors.

An Olympic hero stripped of his medals is buried in a town he never visited, which took his name after his death.

A daring D-Day assault by U.S. Army Rangers is commemorated atop the high cliffs of this strategic point.

An effigy of a trapped paratrooper dangles from a Normandy church to commemorate one remarkable D-Day event.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

This picturesque horseshoe weir was first built in the 1600s to prevent flooding in the town of Bath.

An overlooked memorial honoring the local Washington residents who died in World War I.

Look closely and you’ll notice that the color changes a third of the way up the tower.