The ancient tomb acts as a calendar that keeps perfect time.

Possibly the oldest of Britain's ancient henges is also one of its most stark.

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

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

These haunting ruins of a 700-year-old Prehispanic city have witnessed centuries of wars and massacres.

These spectacular, symbolic serpents lie within the shadow of the Great Temple.

These mammoth-yet-narrow crevasses in the Earth are perfect for taking an otherworldly swim.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Built on the remains of one the Incas’ most important gathering spots, this square keeps the spirit of a fallen empire alive.

A fantastical and futuristic temple of light built from nine monumental glass veils.

A series of waterfalls so massive they straddle the border of Argentina and Brazil.

Mysterious lost empire of the Silk Road.

In the Middle Ages, villagers would sound this stone trumpet to boost fertility and coax fish to shore.

The largest stone moai on Rapa Nui.

The world's most remote airport.

The air force base preserves its scars from the Japanese attack on Pearl Harbor.

This dazzling Buddhist temple was constructed from over one million ceramic tiles salvaged from a British shipwreck.

Subterranean place of worship in Indonesia.

This massive complex is made up of hundreds of smaller temples that date back to the ninth century.

This fountain was once heralded as the largest in the world.

An opal mining town in the middle of Australia where people live, worship, and shop underground.

The longest fence in the world stretches over 3,000 miles to keep the dingoes out.

Clusters of huge boulders in the Australian Outback.