Abandoned railway line circling the city of Paris.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

Once the most densely populated place in the world, this island is now a ghost town.

An enormous, inside-out glass globe built in 1935.

The middle finger of modernity.

The old Route 66 town straddling Texas and New Mexico died along with the Main Street of America.

A 16th-century horror show built in a lovely Italian garden.

An unusual round church in London with a Templar past.

The largest of London's subterranean rivers and once a mad, bad center of London life.

New Orleans' famous cemetery, located on the site of a former race track.

This historic "City of the Dead" lies prominently in the center of New Orleans' famous Garden District.

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

The final resting place of New Orleans' most famous voodoo priestess.

Thousands of exquisitely carved stone water storage wells, hundreds of stone steps fill this exquisite medieval stepwell.

A 1,500-year-old, 3-story subterranean city where ancient Persians took refuge in times of war.

An enormous playhouse designed to look like 21 stacked Lego bricks, with another 25 million colorful Legos inside.

Natural cathedral designed by Italian artist Giuliano Mauri.

Natural time capsule containing an alien ecosystem.

The 19th-century pharmacy (now a used bookstore) was featured in James Joyce’s "Ulysses," and has changed very little to this day.

Thousands of well-dressed mummies below a monastery.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

This landmark church concealed a crypt packed with bones that was discovered thanks to the London Blitz.

A church of bones, decorated with 40,000 human skeletons.

An 18th century monument regularly tagged with unsettling graffiti referencing a 1940s unsolved murder.