The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

A museum dedicated to the alleged Roswell Incident.

A library of rare occult books in Los Angeles.

The abandoned husk of a mental institution that failed to save a Jazz Age icon still sits nearly unchanged.

This unique structure in suburban Austin is made up entirely of other people's castaways, and constantly changing.

An abandoned castle owned and ignored by Masons carries a cursed history.

This abandoned asylum was once a state of the art facility before devolving into one of the most deadly mental institutions in American history.

The oldest cemetery in New Orleans, resting peacefully for over 200 years now.

An emporium for the weird, creepy, rare, and just plain gross.

Continuing the tradition of the dime museum in style.

Medical and zoological curiosities for sale.

A 100-year-old purveyor of curiosities, curios, and kitsch featuring mummies, shrunken heads, and a Fiji Mermaid.

Nonprofit art center that promotes outsider, intuitive, and self-taught art.

This cave holds a surprisingly colorful variety of geological oddities.

Hidden away in the city of Madison, Wisconsin is a nearly forgotten home that Frank Lloyd Wright built for a childhood friend.

Tour the luxe "glass cage" that inspired and unnerved the architecture world upon its debut.

A six-story-tall golden pyramid, surrounded by a moat.

This modest post office sits on the site of H.H. Holmes' famous murder castle.

A haunting statue called "Eternal Silence" has quite the reputation among visitors with active imaginations.