The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.

An ancient necropolis of magnificent tombs.

An enormous and lavish Gothic church in Czechia.

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

A huge cathedral single-handedly constructed by one eccentric monk.

A Museum of Psychiatry in a still-operating mental institution.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

The highest point in Belgium is a staircase to nowhere.

Petting this mysterious iron monkey supposedly brings good luck.

Brussels' favorite peeing boy has a sister.

A little sculpture with a large wardrobe.

Only museum in the world devoted to bookbinding and book arts holds a permanent collection representing five centuries.

The tiny Belgian town's ancient version of Mardi Gras involves eerie wax masks, sticks for warding off evil, and ostrich plume hats.

The vast chamber inside this abandoned cooling tower looks like something out of a sci-fi dystopia.

A magical and peaceful ruined Cistercian abbey in what is now southern Belgium.

This collection of lurid religious statues tell the tales of a saint who stood down the devil.

Earth's rocky history has rarely glittered so brightly as it does in this Spanish museum.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

An ancient Egyptian temple in the middle of Madrid, Spain.

A Belgian self-built tower inspired by the Bible and ancient civilizations.

This abandoned Belgian fortress is purposefully being left to nature.

This giant urban staircase was built to keep the city's brave fighting men from getting waylaid in the red light district.

A marble Lucifer hides behind the pulpit of this Gothic cathedral.