A stately palace has been converted into the world's largest cannabis museum.

On the wall of this medieval walkway, a symbol of the Spanish Inquisition.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

An unusual stroll through gentlemen's erotica demonstrates that pornography is timeless.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

One of Antoni Gaudí’s earliest buildings, built between 1886 and 1890 for the industrialist Eusebi Güell.

The now-abandoned Fascist summer colony served a dark purpose during World War II.

The former 1920s mansion of a prominent Catalan developer was used as the Soviet Embassy during the Spanish Civil War, and there is still a bunker below the garden.

An architect transformed this abandoned cement factory into his castle-like workshop.