The remains of the left arm of the levitating philosopher-saint are kept in a 13th-century Neapolitan basilica.

The relics of dozens of martyrs are stored in a single chapel.

Dug as a secret royal escape route, the tunnel became a wartime bomb shelter and dumping ground for vintage cars.

Spinning silently in the lobby of an Art Deco masterwork is a massive vintage model of the Earth.

The smallest island in Manhattan is a manmade landfill dominated by a Buddhist peace arch.

A fire station-turned-church-turned-museum dedicated to the work of seminal light artist Dan Flavin.

This abandoned five-star hotel is now a five-star urban exploration destination.

A magical sinkhole on the Yucatán Peninsula is adorned with mini waterfalls and hanging vines.

A terrific purveyor of natural history objects and curios.

This exemplar of modernist architecture is meant to captivate and inspire students of the Cooper Union.

A winding cave grotto walkway built to provide employment for veterans after World War I.

A house of bones — but nobody is quite sure to whom they belong.

This vintage weapons display would be the perfect place for bibliophiles to hold out in a zombie apocalypse.

A woodland close to England's "most haunted village" has been the site of many unexplained events and deaths.

During the heyday of fishing in Hastings, there were more than 100 of these storage facilities.

From battleships to Roman vessels, this museum explores the depths of shipwrecks in the region.

A Montreal deli that was so beloved that it was allowed to circumvent their laws of language.

Montreal's giant farmer's market is a foodie's best friend, especially in the winter months.

Designed by Buckminster Fuller, this relic of the 67 Expo survived fire and ice.

This 1967 experiment in modular architecture was designed to be a new model for urban living.

Henry VIII's forgotten castle was built by the gunpowder-obsessed king to be defended solely by cannons.

Underneath the bustling city streets, a hydroponic farm grows unique herbs in an urban oasis.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

Discover the taste of mold.