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

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.

Hop aboard a charming bog train to explore this rare open-air museum of peat.

The gargoyles and grotesques of the 21st century are here—22 emoji built into a new building in the Netherlands.

The history of sea-faring refuse and disaster is on cramped display in this Netherlands folk museum.

This steel frame is a skeletal mirage of a lost 16th-century stone building.

Its town washed away centuries ago, this lonely tower by the sea tells the tale of a mermaid and a curse.

Two gravestones clasp hands over the religious divide.

Pull up and have a drink at a museum filled with hundreds of years worth of shipwreck artifacts.

This miniature take on the Kremlin is one Dutch man's retirement project.

A market built atop boats is one of the few floating holiday markets in Europe.

Take a stroll through the hellish grotesques of Hieronymus Bosch in this elaborate Netherlands church.

The ruins of this Dutch castle sit atop a labyrinth of once-secret tunnels and passageways, dating back over 900 years.

This Netherlands museum holds a gloriously mechanical collection of ornate musical automata.

Inspired by "The Starry Night" this Dutch bike path turns into a glowing work of art each night.

An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

This gorgeous reading room houses the oldest and largest art history library in the Netherlands.