An underground mansion with fruit-bearing trees and grapes growing beneath the surface of central California.

A "gravitational anomaly" located in the redwood forests just outside of Santa Cruz, California.

17th century puritan church with connections to the Salem Witch Trials.

An underground city of salt.

Saintly bones pressed into a wax effigy of a Catholic superstar.

The mummified relics of an American missionary.

This former Masonic lodge has been transformed into part museum, part bar, all awesome.

Inside this former medieval prison is a collection of objects designed to inflict unbelievable pain and suffering on the human body and mind.

Christ's blood preserved in a Belgian town.

A 19th-century shrine covered with prosthetic body parts as votive offerings.

A island reachable by a causeway at low tide is possibly one of the earliest Western European locations to be identified in text.

Sparkling, calcite-covered skeletons of children who may have been sacrificed to appease an angry god.

A contemporary art installation housed within a Gothic cathedral.

Skeletons dressed in extravagant 18th century royal costumes cavort in the aisles of this German basilica.

An indigenous take on European design creates a stunning visual overload.

This solitary monastery may hold the remains of Vlad the Impaler (but probably not).

This little-known relic crypt holds stolen parts of a Roman Empress.

An enormous dragon scales the walls of this 17-story temple.

A historic chapel filled with colorful murals and a colorful past.

A town church once nearly submerged by the damming of a river is now hauntingly visible as the water recedes.

A dreamlike medieval church dug into the tuff rock, with unusual carvings and possible traces of the Templar knights.

The ruins of a medieval monastery built on a perilous slope.

This 15th-century Serbian Orthodox monastery also contained a school for illuminating manuscripts.

A strange house built only at night, with rumored mystic inspiration.