The "Great Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

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

This architectural oddity is an oasis of green on the outskirts of Valencia.

This abandoned viewing platform has become a monument to unnecessary government spending.

Vibrant street art created with mixed media.

This amazing example of Valencian Art Nouveau looks more like a cathedral than a public market.

An ancient Roman theatre restored to its former glory in the Spanish city of Cartegena.

The world's first electric battery-powered submarine.

An eerie collection of the surviving structures from a past celebration of the future.

A 16th-century Andalusian palace.

The world's largest wooden structure.

A monument at Alicante Marina honors a little-known hero of the Spanish Civil War.

Legends surround this natural rock formation that looks like a Moorish king wearing a crown.

A stone slab in Madrid marks the point from which the distances of Spain's national roads are measured.

An ancient Egyptian temple in the middle of Madrid, Spain.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

Mountain where Jesus was first tempted by the Devil.

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 was finally completed in 2026—a century after the death of its architect.

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

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