St Bernard de Clairvaux Episcopal Church, better known as one of the oldest European buildings in the Western Hemisphere.

An underwater city for the dead.

Gladiators battle and chariots race daily in the ruins of a once-great Roman city.

An ancient city hidden in the heart of the Sierra Nevada mountains.

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

Three sinkholes filled with warm, crystal-clear water reached by a horse-driven cart on an old train track through the jungle.

This beautiful Miami garden was designed as a laboratory for tropical plants.

An all-female order shares an ancient culinary art with visitors at their mountaintop monastery.

South Korea's love of the silly photograph is on full display at this goofy collection of trompe l'oeil paintings.

Giant disc-shaped gate took 20 men to close off this city in Madagascar.

This picturesque island graveyard is the final resting place of dozens of notorious pirates.

The centuries-old trees lining both sides of this dirt road may become Madagascar's first natural monument.

This scalding hot river was thought to be a myth until one geoscientist made it his quest to study the mystical waters.

The mortal remains of an estimated 70,000 people lie in the basement of a monastery in Lima, Peru.

Keshwa chaca, among the last handwoven Incan bridges, crosses Apurimac Canyon in Peru.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

Ten shipwreck-shaped chalets lie along the sand dunes on Namibia’s Skeleton Coast.

This "dead marsh" sits among the largest sand dunes in the world, a forest frozen in time.

A desert that rolls right up to the ocean, where it's so dry animals live off the fog.

The remains of diamond fever taken over by the desert.

The caldera of this mini-volcano has been turned into a naturally heated mud bath.

A sinkhole and now a swimming hole, too, full of dazzling turquoise water.

This spectacular mosque houses the second-largest chandelier in the world.

This bazaar is one of the oldest in the Arabian world.