According to local lore, this narrow passageway through two large rocks was accidentally created by the devil himself.

Legend says a primate-like cryptid prowls this otherworldy sliver of the Louisiana bayou.

Ten acres of the Kula Forest Reserve make up this wondrous state park.

One of the most unusual geological features, recognizable from a dozen hit movies.

A blacklight mini-golf fever dream pays tribute to the iconic rock band.

An optical illusion found amid a logged redwood forest.

A beautiful, dense forest in the shadow of Mount Fuji, with a tragic reputation.

The largest catacomb system in the world.

Australia's largest traditional hedge maze features a Great Gnome Hunt.

The twists and turns of this serpentine maze are over 170 years old.

Possibly the world's largest hourglass only needs to be reset every New Year's Eve.

The only free-standing, vertical sundial in the US was keeping standard time before it was even invented.

There has been an astronomical clock on this spot since the 14th century.

Macabre astrological automaton clock dating to the late 1400s.

This Sumatran root bridge took almost 30 years to knit itself together.

Two small chapels housed inside an ancient tree.

Natural cathedral designed by Italian artist Giuliano Mauri.

Living trees form the structure of an open-air palace.

The haunting, dilapidated remains of a former poorhouse on Staten Island's Greenbelt.

Deep under Manhattan is the largest construction project in city history. So far, the project has taken the lives of 23 workers, or "a man a mile."

Virgil's many-mouthed gateway to the underworld.

Steaming blood-red hot spring from hell.

A deadly ancient portal to the underworld.

According to one local tradition, the entrance to the Voodoo underworld can be found in New Orleans through seven gates scattered throughout the city's French Quarter.