A lovely look back at the manufacture and use of paper in all its forms.

The haunting complex honors the millions of Ukrainians who died in the forced famine under Soviet rule.

The medieval prince founded the first library in Ukraine at Saint Sophia's Cathedral where he was interred.

An abandoned socialist utopia built in the late 19th century.

This 15th-century aqueduct with distinctive pointed arches was used for irrigation in the Vinalopó valley.

This site is both a remarkable reminder of the town's mining history and a fantastic government blooper.

A landmark in the history of technology and computing is hidden in a tiny Baroque chapel.

When this funny little building went up in the 19th century, most people thought it would simply fall over.

A massive mausoleum towers over the gravestones in a 19th-century Italian "model village."

These three pillboxes still remain as a witness of the Spanish Civil War in a park of Madrid.

Inside this church are the alleged remains of the patron saint of lovers, epileptics, and beekeepers.

In the fictional world of Kcymaerxthaere, celestial wonders marked a portal to a powerful route of travel at this site in Madrid, Spain.

Just like in Hollywood, Madrid has also a forgotten walk of fame.

This fascinating and poignant museum chronicles every imaginable aspect of Spanish colonialism in the Americas.

This small and often-overlooked museum holds some of Spain's finest artistic treasures.

The unfinished final resting place of some of Spain's most prominent politicians.

A reproduction of the famous prehistoric cave paintings is hidden underground at the National Archaeological Museum.

A rare set of strings by famed instrument maker Antonio Stradivarius is on display in the Royal Palace.

A whimsical brother of the nearby Fallen Angel statue takes the falling part quite literally.

Also known as the Square Colosseum, this building is a prime example of fascist-era rationalist architecture.

This postmodern apartment block was designed to be a vertical neighborhood.

The remains of the second-oldest zoo in Europe can be seen within these library gardens.

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

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