Not far from Madrid, a set of perfectly preserved trenches date back to the Spanish Civil War.

This ancient Visigothic church might hide an ancient treasure.

Two large eyes painted anonymously on a mountain overlooking the city pay homage to an old legend.

An independent naturist colony amidst 1000-year-old ruins.

The ruins of an ancient Celtiberian town with incredible rock-cut buildings and a Roman aqueduct.

Whimsical sculptures and caves chiseled by nature over the millennia.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

A curious memento mori hangs in the magnificent Cathedral of Segovia.

Behind this pair of dragon trees, there is a tragic story of lost love.

This mansion oasis contains gardens, sculptures, and fountains just off the busy Plaça Kennedy in Sant Gervasi.

A long strip of fossil-filled limestone makes up this natural bridge above a rushing stream.

Peek into a cave of giant, glimmering crystals.

According to tradition, King Phillip II supervised construction of the seat of his empire from this seat carved into rock.

This Arab fortress was once the largest citadel in Western Europe.

An ornate tower shows off a local artist's architectural flair.

An outsider folly near Madrid.

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

A magnificent, long-abandoned castle built in the wake of the reconquest of Spain.

A breathtaking and biodiverse wilderness in the mountain setting of Ernest Hemingway's "For Whom the Bell Tolls."

You can soak in three relaxing pools filled daily by the tide.

This abandoned, turn-of-the-century astronomy hub is now the subject of more photographs than it ever took.