Natural stone arches form a walkable "cathedral" at low tide, then disappear entirely when the water returns.

Seaside ruins of a settlement that date back to the first century B.C.

Remarkably intact Roman stone fortifications have encircled this Spanish city for centuries.

Open air sculptures by an eccentric and loin-clothed hermit.

The remains of an encyclopedic sculpture garden later used as an internment camp.

The oldest Roman lighthouse still in use.

Giant granite sculptures representing family on the northern coast of Spain.

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.

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.