The world's oldest bookshop still in operation.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

This small chapel is built of human bones and decorated with a golden skeleton.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

A submerged village appears when dam levels drop.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

Houses are tucked between, on, and underneath giant boulders.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

Local legends say that fairies used to dance in the moonlight here and invite handsome young men into their grottoes.

The quiet field that inspired one of the most famous songs of all time.

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

You'd never know the houses at 23-24 Leinster Gardens were fakes—until you see the train tracks on the other side.

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

This tiny little pool is said to be home to a malicious mermaid named Jenny Greenteeth.

This silent sentry in the crypt below a large Gothic cathedral is often knee-deep in water.

The Origin of On the Origin of Species.

These lovely Turkish-styled baths were brought back to life after winning a reality show competition.

The ghosts of Britain's telecommunication past sit rusting away in a small village in England.

A midnight snack that lights up the night.

The cedar tree in Highgate Cemetery earned its title by accident.

One of the few standing Roman lighthouses and a labyrinth of tunnels are a couple of the secrets at this historic castle.

A open air theatre built on a cliff by an eccentric British woman.