This portion of a lovely Belize beach is infested with (harmless) sharks and rays.

Sparkling, calcite-covered skeletons of children who may have been sacrificed to appease an angry god.

A massive underwater sinkhole made famous by Jacques Cousteau.

A Buddhist theme park brings you a Buddhist version of Hell.

Think you have a tough job? Try carrying 200 kilos through a cloud of sulfur down the side of a volcano.

Few people have ever heard of, let alone visited, one of Turkmenistan’s most impressive natural attractions.

A cave covered with bizarre stalactites of cloth.

An eccentric dictator's take on a Turkmen version of Disneyland.

This famed Silk Road oasis was one of the largest cities in the world before it was destroyed by a Mongol horde.

A fiery crater has been burning in the Karakum Desert since 1971.

A cemetery with goat-horn bedecked gravestones.

This cavernous swimming spot doubles as a home to the largest known colony of bats in Central Asia.

A reportedly haunted 14th-century church is curiously facing the “wrong direction.”

Virgil's many-mouthed gateway to the underworld.

A former copper mine which became a truly unsuccessful prison.

This Vietnamese hell cave lets visitors take a walk through a devilish underworld full of demons.

This funky former tobacco factory is one of the most striking examples of Madrid's cultural diversity.

The only urban monument in the world designed by the great surrealist painter Salvador Dalí.

One of the world's oldest universities houses an incredible collection of anatomical models, mummified body parts, and human bones.

This amazing abuela became a diehard metal fan late in life and an icon of Madrid's '80s rock scene.

The earliest known map to show America, discovered by accident at a Paris bookshop.

The morbid items in this small and hidden museum are not for the weak stomached.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

A haunting collection of the vanished and disappearing natural world.