An abandoned, unfinished mansion on grounds strewn with lava rocks.

A beautiful, creepy 19th-century castle stands incongruous in rural Vermont.

An eerie, abandoned military base engulfed by nature and graffiti is now home to a local park.

A mysterious drive-in nestled in the forest that leaves little to the imagination.

This former mining hub holds a surprising abundance of undisturbed relics from the Old West.

This giant steer-skull edifice refuses to die.

The sole remaining outpost of a once-thriving South Carolina chain still sells “pic-a-nic” baskets.

Possibly the world's only drive-in movie theater with an attached motel.

There's a crumbling old mansion inside the Smithsonian National Zoo.

Behold the rickety wooden glory of the world's oldest operating roller coaster.

The park preserves a single, rare species of carnivorous plant that spells doom for unsuspecting insects.

This unique historical monument features large concrete spheres designed to resemble fallen stars.

A quirky Poe-themed joint on an island keen to celebrate its overlooked connection to the famous writer.

In the bowels of a 19th-century brewery lurks a fine-dining restaurant offering an array of themed feasts.

Collection of skeletal systems from the "world's leading supplier of osteological specimens."

This jail which was in service for over a century is now open for curious visitors.

This stunning gothic ruin was a casualty of the Indiana steel industry crash.

A six-foot pair of socks hangs from a drawer of the world's largest bureau.

A century-old cabin off of Highway 30 touts an unusual construction material: dinosaur bones.

A Wild West jailhouse that slid down the mountainside.

An unrealized Taoist palace left abandoned in a Houston suburb.

The graffiti-covered remnants of a former triangulation station are balanced precariously on this California peak.

Other-worldly rock formations and ancient fossils abound in this unique stretch of Nebraska badlands.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.