The platform atop this verdant volcano was built with the help of a royal elephant.

The site of abandoned cable car system provides expansive views of Tutuila and nearby capital Pago Pago.

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

This Soviet-era athletic and recreation facility is the highest ice skating rink in the world.

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

Lonely minaret stump of a destroyed city.

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

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

This unique wooden mosque resembling a Chinese pagoda was said to be built without the use of nails.

Nicknamed Kazakhstan's Grand Canyon, this natural wonder lies east of Almaty near the Chinese border.

Scale model of St. Peter's Cathedral (Rome) in the middle of a small Dutch town.

The ruins of this Dutch castle sit atop a labyrinth of once-secret tunnels and passageways, dating back over 900 years.

The ancient heart of Tunis is an enormous maze of narrow streets and alleyways.

Some believe this abandoned Brutalist masterpiece inspired George Lucas's Sandcrawler.

An ancient Phoenician citadel once stood at the site where Queen Dido first landed, according to legend.

This dizzying span over the ancient Algerian city was once the highest suspension bridge in the world.

Classical ruins that remember ancient Rome's presence in Africa.

An extraordinary mix of Phoenician, Roman, early Christian, and Byzantine ruins beautifully set overlooking the Mediterranean.

The original resting place of Queen Cleopatra and Mark Antony's only daughter.

The first statue to be added to Saint Peter's Square in over 350 years is an ode to migrants and refugees around the world.

Along a manmade hexagonal lake lies what was once the main port of ancient Rome.

This massive monument towers over the city as a constant reminder of the lives lost during Algeria's hard-won war for independence.

Yup, that's a 330-foot yacht passing over the highway.

A striking symbol of the Bulgarian capital.