The fairy tale castle of the "fairy-tale king."

An underground city of salt.

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

An eccentric inventor's castle home with its own indoor weather system.

A genuine Little Shop of Horrors.

A 18th century graveyard and its astonishing cortege of macabre iconography.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

Tiny effigies of the victims of Edinburgh's famous Anatomy Murders.

A book bound in the skin of an infamous criminal, along with countless other specimens.

One of Scotland's most important modern structures, it just made the '100 Most Endangered Sites' list.

This grave resides at the crossroad of three parishes.

The world's largest collection of witchcraft regalia.

80 years of the Battle of Peasholm on a small English lake.

The curious and tiny collection contains some very odd objects.

This ancient church, rebuilt at least 3 times, is flanked at all sides by history.

WWII artifacts, including the building itself.

Below a historic English market town lies a secret underground city complete with kitchens, laundries, storerooms, and an underground lake.

A perfectly running 230-year-old silver automaton and music box.

An Irish church where an 800-year-old mummy is reaching out of his coffin as if to shake hands.

World's largest working waterwheel has been around for over 150 years.

Unusual British home built to disguise a water tower.

A boutique perfumery fashioned to look like a Victorian-era shop.

Grotto replete with mystical designs laid out in glued shell mosaics.

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