Beneath the mossy overgrowth covering this once-sprawling campus lies decades of history and the secrets that come with it.

The only example of a Paris Métro sign in use at a subway station outside of the French capital. 

The vaulted ceiling is home to a scurry of “squirrelgoyles.”

This restored house is like a time capsule of the president's unconventional inauguration.

Located in a Civil War era building, this café is engrained with the spirit of Edgar Allen Poe.

The remains of a religious colony, its amusement park, zoo, and baseball empire.

Hell on Earth is actually a small town in Michigan where anyone can be mayor for a day.

Abandoned concert venue legendary for its rock counterculture.

A man used his Civil War-era fortune to build this sanctuary in memory of his wife.

A temple devoted to inner esoteric mysteries located in a California commercial strip.

One of the oldest of its kind.

Old neon signs from the City of Brotherly Love provide a snapshot of the city’s evolution.

The body of St. John Neumann and his collection of hundreds of relics, on display in a Philly church.

This museum boasts a bucket of teeth and tells the tale of a 20th-century dental circus.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

A clone-tree in Washington Square Park sprung from seeds that went to the Moon and back.

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

A museum dedicated to the strange and extravagant costumes and memorabilia of the mummers, a tradition older than Philadelphia itself.

Huge masonic hall in Philadelphia with lavishly themed rooms.

This fortress was designed to prevent a Nazi invasion but was never used.

A celebrity from the late Cretaceous period.

A computer bug so primitive it was an actual insect.

Cold War intelligence agents monitored communist embassies from an attic in a former pigeon coop.

A historic freight system that found the true gold rush is in tourism.