Cliffside houses provide a spectacular view from their perch above the valley.

A modernist church in an ancient village.

Infamous and now demolished panopticon prison built by its former inhabitants.

A huge cathedral single-handedly constructed by one eccentric monk.

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

What almost started out as a spite house became an eccentric's found object masterpiece.

Wonderland replication in progress by one persistent man.

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

Three bridges and one giant canyon make up this fantastic Spanish settlement.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

A beautiful but toxic fountain of mercury.