A stunning 18th-century site where pilgrims ascend by a series of punishing stairs only to return via funicular.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This small chapel is built of human bones and decorated with a golden skeleton.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

This demon atop the Notre-Dame de Paris looks utterly bored.

Skeletons, medical artifacts, and other obscure and precious treasures all displayed in a wooden pharmacist's cabinet.

One of the largest ossuaries in Spain is packed from floor to ceiling with bones.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

The soulless eyes of 82 bronze children stare on forever in remembrance of a horrifying World War II massacre.

Mysterious painted skulls in Moravia.

Europe's second largest ossuary wasn't discovered until 2001.

A steampunk-styled three-floor factory churning out art, activism, and electronic beats.

A collection of anatomical samples from one of the first anthropologists to suggest that humans reached North America by crossing the Bering Strait.

Two stunning 17th-century libraries and a cabinet of curiosities.

The short-lived railroad town in central Oregon has been abandoned since the 1930s.

William Faulkner kept his beloved estate wild and untamed.

This New Orleans statue of a portly figure in a goofy hat pays homage to a classic of satirical literature.

This historic New Orleans cemetery is the final resting place of members of the Independent Order of Odd Fellows.

A museum of unusual collections, mini-towns, and a half-dog, half-alligator.

The above-ground crypts at this Catholic cemetery face north-south instead of the usual east-west.

Once defending the city of New Orleans from invasion by sea, this fort faces an uncertain future.

By day this New Orleans square is for pedestrians, but by night it is a kingdom of kittens.