Though it may look like it’s missing its outer shell, this skeletal cast-iron tower was built to withstand wind and waves.

Stunning Roman aqueduct used for 1900 years and still standing.

The ruins of a bombed medieval village memorialize the destruction of the Spanish Civil War.

Mountain where Jesus was first tempted by the Devil.

This serene, turquoise lake in an extraordinary nature reserve showcases a rare natural phenomenon.

Windblown rock formations in an ancient Roman quarry.

Colorful clay cliffs tower over an unofficial nudist beach on Martha's Vineyard.

The recurring nature of this geographic feature might make it unique in the world.

The birthplace of both the Atomic Age and Godzilla, and the namesake of the bathing suit.

The world's seventh-largest coral reef contains an incredible amount of biodiversity.

Send a postcard while vacationing with Satan.

Europe's largest natural bridge has a 19th century royal chateau built into its side.

Tens of thousands of ancient rock carvings hidden in the heart of a French national park.

The courtyard of this small Marinid madrasa is a dazzling example of intricate Islamic architecture.

The true depths of these stunning Moroccan caves are unknown.

Beauty and history abound in this remote West Texas canyon.

This hidden pre-Columbian rock art depicts a whale hunt.

A charmingly unusual prefabricated metal church designed by Alexandre Gustave Eiffel.

An abandoned whaling station on an active volcano offers hot springs in Antarctica, surrounded by ruined giants of industry.

This picturesque monastery at the base of a cliff is a peaceful oasis open to all visitors.

Bridge that died in war and was resurected.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

Monasteries on rock pillars, once accessible only by frayed ropes.

The convergence of two currents makes this a surprisingly pleasant getaway in the Arctic Circle.