10,500 square feet of pinball housed in former dollar store and home to the last playable "Thunderball."

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

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

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

The origin of this mechanical boy was a mystery until he revealed his maker by writing it in perfect cursive.

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

This collection of odd proofs of concept is like taking a walk through the imagination of a Victorian engineer.

This abandoned Poconos resort is haunted by a history of kitschy romance and a violent fugitive.

These beautiful ruins deep in the Pennsylvania woods are thought to have been a ski lodge or a speakeasy, but no one really knows.

Collection of trolley cars in the woods represent one man's attempt to preserve transportation history.

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

An indoor miniature village and labor of love for Laurence Geiringer, a model railroad enthusiast.

A toxic ghost town sitting atop a massive coal fire.

This lush forest valley was once mined for lumber to the extent that it was once nicknamed "The Pennsylvania Desert."

"Dark Sky Park" is heaven on Earth for astronomers, one of the rare U.S. locations with no artificial light pollution.

The world's brightest bioluminescent bay.

A subterranean playground in an abandoned slate mine.