An abandoned network of military bunkers and tunnels open for anyone willing to descend into the darkness.

This dilapidated ship carcass covered in trees is a striking sight.

The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

A museum dedicated to the history and exploration of both popular music and science fiction.

This magnificent Japanese garden provides a moment of Zen in rural Vermont.

An artist sees trees as a medium for sculpture.

This crumbling UFO is one of only a few remaining "moveable ski chalets" of its kind.

One of the oldest living oak trees in the Southeast.

This tiny cottage surrounded by railroads is the oldest surviving structure in Fairmount Park.

Francis Julius LeMoyne built this crematory in 1876; he was the third person to be cremated here.

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

A larger-than-life statue of America's favorite sundae marks the place it was invented.

The residents of the Neighborhood of Make-Believe live without much fanfare within the Pittsburgh Children's Museum.

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

Enjoy a slice while browsing the world's largest collection of pizza memorabilia.

The remains of a community that was forced to move for a dam that never materialized still rot in this Pennsylvania park.

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

The universally beloved children's television figure is interred on a high hilltop in one of western Pennsylvania's oldest cemeteries.

Eccentric concrete mansion and museum designed and built by hand from the inside out.

Huge masonic hall in Philadelphia with lavishly themed rooms.

A beautiful oddities shop crammed with strange and morbid curiosities.

Celebrate the history of the rich and truly misunderstood relationship between man and pigeon.

Where hills of dirt conceal the burial ground of one of the most powerful ancient Native American societies.

American bison herd descending directly from a Bronx Zoo breeding program that saved the species from extinction.