This retro, UFO-like structure is a remnant of the Soviet-era circus.

Built entirely of interlocking pieces, construction of this Chinese Muslim house of worship required zero nails.

According to myth, there's a bloody explanation for the beautiful bright red color of this rock formation set amidst alpine vegetation.

A boulder carved into the shape of the cosmonaut's head.

This mysterious complex of abandoned yurts and fading murals was meant to be a center of science and spirituality in Kyrgyzstan.

A breathtakingly steep set of stairs is carved directly into the face of the sea cliffs of Bonifacio.

At least according to the Guinness World Records.

The water of this well in Toledo lost its sweetness after the death of a young love.

The atmospheric ruins of a historic church can be found on a hill above the city of Oviedo.

The abandoned ruins of a failed resort hide on this verdant, picture-perfect island.

A mountain cave is the site of archaeological findings and Paleolithic rock art.

The oldest scientifically dated tree in Europe lives on a remote cliff.

This 170-year-old Swiss guesthouse built into the side of a mountain is best accessed by a cable car.

This Arctic storage facility is a secure backup for agricultural biodiversity.

In the northernmost city in the world, it's illegal to be buried because it’s too cold for bodies to decompose.

The forbidden island of the Tuscan Archipelago may still contain buried treasure.

A forgotten "city of water" underneath the famous Trevi district.

This mine was once used to defend the coast from attack during World War II.

Commemorating the landing of William of Orange with his European army on their way to the Battle of the Boyne.

This stone harbor was key to Carnlough's limestone industry.

This village provides a glimpse at rural life in Northern Ireland during the mid-20th-century.

Amazing vistas await visitors to this stretch of coastline.

The highest tides in the world come in and out here twice a day, allowing you to essentially walk along the ocean floor.

An ancient Viking village in North America that predates Columbus by 500 years.