This free, take-a-book shop seems like a trick but isn't.

An abandoned church gets a second life as a massive beer hall and event space.

The maritime museum that boasts the largest nautical library in the western hemisphere.

Ship skeletons haunt Baltimore's waterways.

The trials and tribulations of marking Poe's grave.

A model home in the Medical Examiner's Office in which grisly death scenes are staged to train forensic investigators.

Eighteen miniature death-scene dioramas.

One of the oldest Catholic churches in the U.S., situated just east of Gettysburg.

A vast collection of everyday items amassed by one man.

Rowdy rebels fortified this home during the first popular uprising in United States history.

Captain John Smith thought these cliffs were amazing in 1608 but sharks thought so 20 million years before him.

Bizarre and inspired combination store selling only two items: tires and bibles.

A 300-yard long natural tunnel runs through a ridge deep in the Appalachian Mountains.

Pittsburgh's literal underground railroad.

No one knows who painted this mysterious mural in a Penn State basement.

Enchanting gardens surround a derelict mansion, all hidden in plain sight behind a stone wall.

The land is home to swimming ponies and a legendary 18th-century treasure.

One of the oldest surviving Swedish-American homes in the United States.

What looks like a simple quaint estate in rural Pennsylvania was in the 18th century home to a small monastic community.

These lush botanical gardens employ the most purrfect pest control force.

It marks the spooky spot where the bodies of two young boys were found in the 19th century.

The site of the little-known Pennsylvania battle that sparked the Seven Years' War.

Several times a year, during low tide, two pairs of historic train tracks are revealed on this New Jersey beach.

World War II bunker still standing on the New Jersey beach.