Sweden’s legendary mine with wildly deep tunnels.

This luxury hotel suite is located deep in the bowels of an old mine.

A plaque marks the house in Stockholm where the French philosopher René Descartes lived up until his death.

Stockholm's narrowest alley is barely over two feet wide.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

This small museum nestled inside a souvenir shop is dedicated to Sweden's most well-known toy.

Several cannonballs of mysterious origins decorate two buildings in Stortoget's main square.

An entire shopping mall and industrial terrain named for the time the king of Sweden's car went into a ditch.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

A fantastic Christmas tradition where defecation meets the manger.

A medieval palace holding a millennium of the Crown of Aragon's records

An eclectic collection of thousands of items owned by the sculptor Frederic Marès.

Red, white, and blue painted steps along with a Union Jack celebrate the outcome of Gibraltar's 1967 referendum.

Single runway interrupted by a busy road that cuts across its middle.

This unassuming chapel in Portugal plays host to a ghoulish collection of bones.

Perhaps the most spectacular grotto along the Algarve coastline.

An abandoned tuberculosis hospital said to be haunted by the patients who died within its walls.

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

This enormous censer uses a pulley system installed over 400 years ago.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

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

At night, bats patrol this magnificent 18th-century space in search of book-eating pests.

A unique seaside cave where Aleister Crowley faked his own death.

The corpse bride of Portugal.