An enchanting monastery in the Spanish countryside appears lifted from a fantasy tale.

Holy Grotto of Montserrat Monastery holds one of Europe's mysterious black Madonnas.

Gaze upon chocolate sculptures depicting everything from chariot races to Gaudí's famous church at this shrine to sweets.

This cemetery features modernist statues as strange as its name.

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

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

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

Ancient cave tombs known as the "houses of fairies."

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

A writer's tiny retreat built from salvaged shipwreck timbers.

A picture-perfect town, perfect for blowing up.

These spooky and unusual stone formations create an underworldly landscape.

Built during the Scottish boom in the oil industry, the village was never inhabited.

A nuclear bunker built to shelter the politicians and important people of Scotland in case of nuclear attack.

This Scottish bridge seems to compel dogs to leap to their death.

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

In this historic region, homes and churches are carved into ancient volcanic rock formations.

"Alleys of Stone" form natural mazes in Spanish natural park.

Roman ruins top white travertine terraces formed by ancient hot springs.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

World's first "penitentiary," meant to be humane, drove men insane.

Keshwa chaca, among the last handwoven Incan bridges, crosses Apurimac Canyon in Peru.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

Where Aleister Crowley taught magick in "La Chambre Des Cauchemars," his "Chamber of Nightmares."