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

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

Numerous sculptures set along hiking trails symbolize and idealize the relationship between man and nature.

This cemetery features modernist statues as strange as its name.

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

Beach instrument turned bed and breakfast.

This is not your typical jungle gym.

One of the world's earliest skyscrapers.

What was meant to be a temporary exhibit is now a permanent fixture at the St. Louis Zoo filled with beautiful birds.