Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

A complimentary beverage is offered to the bodega's resident rodents every day.

The world's most elegant power lines.

The defensive tower was built centuries ago to warn locals of Berber pirate attacks.

Single runway interrupted by a busy road that cuts across its middle.

Along the most northwestern point in Africa is an ancient cave surrounded by legends.

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

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

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

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

A public urinal so pretty, it was declared a national monument.

The first declared National Monument in the United States.

The many—66 to be exact—faces of the German forest.

The ruins of an ancient Roman tomb hidden in the basement of a trendy clothing store.

A sharp sculpture made of thousands of pieces of jagged glass.

Legendary site where an evil bishop was devoured by rodents.

A memorial for a young woman and her ghost, which are claimed to have caused countless deathly shipwrecks.

Tiny castle in the middle of the Rhine made you pay to pass.

Hear the quietest sound from across the dome.

The walls of the iconic dome are hollow and have a secret stairway.

A little sculpture with a large wardrobe.

This city square is home to Amsterdam's oldest church and a statue honoring Dutch sex workers.

The world's only museum devoted to the wonders of fluorescence.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.