In an arid region, this beautiful lake in the Aravalli hills is an unexpected delight.

The ancient sauropod tracks found in this former quarry are some of the largest in the world.

Accessible only by boat, this centuries-old island fort never saw troops or combat.

Perhaps the most spectacular grotto along the Algarve coastline.

An eerie site of reverence for those who have completed an epic journey.

This burial cave houses around 100 ancient coffins, neatly stacked to form a massive wall.

These Bronze Age rock carvings are among the oldest in the region.

Mysterious stone faces line a hidden path great for seeing wildflowers, bird watching, and rock climbing.

Three large boulders covered in mysterious carvings and graffiti.

The corporeal remains of Napoleon III's dentist rest under this 15-story obelisk.

Approximately 300 million years ago, a massive coral reef existed in what is now the largest limestone cave in Japan.

At the time of its construction, this hydroelectric power plant was the largest in the world.

This museum is dedicated to the cultural history of tobacco and salt, once monopolized in Japan.

This "cursed house" features secret rooms, hidden vaults, and dark escape tunnels.

The ruined abbey includes a rare surviving example of a monastic latrine.

The 25-million-year-old cavities have perplexed people for decades.

Few of the many visitors to this resort town know of its hidden Maya ruins.

A mysterious, ancient collection of pre-Hispanic petroglyphs hidden deep in the Mexican desert.

A king's bloodstained shirt is among the gruesome collection of artifacts displayed below Stockholm's Royal Palace.

This engineering marvel is the longest bridge in Canada and one of the longest spans in the world.

One of the world's most advanced radio observatories sprawls across the Atacama Desert.

The museum houses "the most studied meteorite in history," among other geological oddities.

It's where the final scene of the beloved Tom Hanks movie was filmed.

A throwback train ride transports passengers through one of the lesser-known national parks in the country.