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

The world's oldest bookshop still in operation.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This crumbling Portuguese ruin overlooks the populace it once ruled.

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

"Portugal's Stonehenge" is made up of nut-like stones aligned with the heavens.

An abandoned mine now resembles a post-apocalyptic landscape of derelict buildings and blood-red pools of water.

Dead weights honor the dead of Portugal's fishing industry.

This small chapel is built of human bones and decorated with a golden skeleton.

A towering monument in Spain has proven to be more labor-intensive than initially planned.

Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

Two towns are linked by an engineering marvel masquerading as a boring suspension bridge.

Giant topiary dog once played a role in a terrorist bomb plot.

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.

The Cathedral of Salamanca has a number of unusual carvings but none so surprising as a modern astronaut.

One of the most spectacular bridges in Spain spans a narrow chasm that divides the city of Ronda.

The world's largest wooden structure.

A lush indoor jungle fills this bustling Madrid transportation hub.

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

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

This cemetery features modernist statues as strange as its name.

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

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