Part of one of the largest flooded cavities on the planet, and littered with prehistoric animal bones.

These termites have an large and deadly abode—impressive by day, dazzling by night.

This small group of sand dunes manages to pack in a strange rainbow of colors.

Réunion Island's highest point is a 2 million-year-old volcano and a paraglider's paradise.

Over two-thirds of the world's population of giant tortoises live among this coral formation.

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

Fabulous formations, weird and wonderful wildlife.

An ocean in the making, in the Ethiopian desert.

The Voodoo Superstore of the world.

This series of rope-style bridges brings visitors into a jungle layer that is usually reserved for birds and monkeys.

Venice's "Island of the Mad."

Venice's island of the dead.

The beautiful baroque library of the Hapsburg empire.

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

This former insane asylum now holds a pathological anatomy museum.

A small museum filled with over 1,000 clocks, and one particular clock calibrated to run until the year 9999.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

Museum dedicated to the terror regimes of Hungary.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

Once the path of a railway tunnel, now home to thousands of glowing insects.

Dilapidated ruins that once treated a notorious young serial killer, currently hosting vandals, squatters, and ghost hunters.

Australian Lake set aglow by Noctiluca Scintillans.

An Australian lake whose pink hue defies scientific explanation.

A part of the world's largest marsh seems to be growing bright red Martian grass.