A medical facility that has been kept frozen in time.

This elaborate estate contains a stunning marble aviary, a sunken conservatory, and a magnificent music room with a two-story pipe organ.

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.

A journey through a curious collection of oddities and wonder.

This macabre shop, filled with art, oddities, and taxidermy is hidden in the heart of the French Quarter.

It's unclear what caused the fire that led to this opulent hotel's demise.

The hidden jewel of Disneyland: a members only playground for the Disney elite.

Heralded as the oldest statue in London.

When construction began on this hotel, developers were surprised to find the ruins of an ancient civilization.

The only residents of this abandoned housing development full of identical castles are stray cats and dogs.

This hidden library of physiological ephemera contains centuries worth of knowledge on the vim and viscera of the human body.

Nikola Tesla's former home contains an homage hidden from plain sight.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

A hidden bar inside an ad agency has a deliberately misleading name, so employees can stay late under pretext of paperwork.

Dedicated to the armor and weapons used by the legendary Japanese warriors.

A busy island at the center of the world that doesn’t actually exist.

A mysterious, weather-beaten bus lies on the coast of Harris, enticing the curious to investigate.

Long-forgotten artifacts give incredible insight into New York's most glamorous hotel.

A mysterious crater-like pond has a spooky tendency to empty and fill with complete disregard to rainfall patterns.

The hidden lair of an alchemist rediscovered in a 2002 flood.

A museum of alchemy and a basement laboratory all housed in an ancient building in a Gothic tower.

Martha's Vineyard's most beloved speakeasy sells late-night pastries.

This Stonehenge-inspired solar calendar stands alongside a landfill, in the middle of the Nevada desert.