Eight naturally mummified bodies in glass coffins are housed in an underground crypt.

One of the world's oldest working clocks is curiously missing the Zodiac sign of Libra.

The chefs at El Diablo use heat generated by an active volcano to cook the food.

More than 300 years old, Kyoto's historic "teahouse" still operates as an invitation-only geisha club.

As can be expected from a centuries old church built in a canal city, the undercroft of this house of worship is beautifully flooded.

This giant wooden treehouse within a sprawling garden has its own eatery.

The restaurant keeps a hidden séance room on the second floor and reserves a table for the spirit of the former owner each night.

Housing the groundbreaking maps and globes of Gerard Mercator.

A huge wooden clock that is so beautiful its creator was forcibly blinded.

Legend says if you stick your thumb in the hole and it gets wet your wish will be granted.

Seventeen oak trees sprout from the roof and walls of this tiny chapel without any visual evidence of roots.

The largest cave chamber in Britain—big enough to fit a whole cathedral inside.

A cave in southern Italy adorned with thousand-year-old Biblical frescoes existed in obscurity until fairly recently.

A scenic canyon with thick forests and historic ruins.

A spiral staircase connects the limestone cave with Pembroke Castle, birthplace of King Henry VII.

The underground sanctuary of a mysterious ancient Roman religious cult contains an exquisite traditional fresco.

It is said the legendary wizard once lived in this sea cave beneath Tintagel Castle.

An army of sleeping knights sculpted by a self-taught local artist beautifully depict an old Czech legend.

Shakespeare, David Bowie, Dr. Who, the Saxons, Druids and Romans are all claimed to have all made their mark on these massive man made tunnels.

Virgil's many-mouthed gateway to the underworld.

Cave on extinct volcano, once home to famous mathematician Pythagoras.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

Figures of unknown origin carved into the surfaces of underground caves.

Holy Hindu shrine in an enormous, monkey-filled limestone cavern.