Millions of glowing microscopic organisms light up the waters of this luminous lagoon.

Stone shrouds of Prince Liu Sheng and Princess Dou Wan of the Han Dynasty, created to preserve their flesh for eternity.

Submerged trees jut ghost-like out of an idyllic turquoise mountain lake.

The world's largest collection of witchcraft regalia.

An island in the middle of a lake, in the middle of a volcano, in the middle of a bigger lake, in the middle of a bigger island, in an archipelago, in the Pacific Ocean.

A wonder of natural limestone formations etched by millions of years of natural interaction between rainfall and rock and air.

An Australian lake whose pink hue defies scientific explanation.

A lake in the middle of the tundra of Quebec is said to be the purest freshwater lake on Earth.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

Paranormal activity on the great lakes.

Limestone caves with spectacular showcase chambers.

A cave network located at the southernmost tip of mainland Greece was once believed to be an entrance to Hades.

Rodin's famous depiction of Dante's 'Inferno', amidst a sculpture garden of many of his other works.

Macabre astrological automaton clock dating to the late 1400s.

The world's highest and most dangerous infinity pool lies at the precipice of Victoria Falls.

Mysterious rocks that ring musically when struck.

Pompeii's less famous neighbor is still revealing her secrets.

The once forbidden "secret cabinet" of erotic art from excavations of Pompeii and Herculaneum.

Two churches shoot bottle rockets at each others' bell towers in an unusual Easter celebration.

Rock-hewn monastery complex with hundreds of cave structures tucked away into the mountainside.

Go surfing on this urban wave, "hacked" by local surfers.

Museum on French naval history, with magnificent figureheads, a historic diving suit, and a boat used by Napoleon.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

A sulfuric hellscape in southern Italy.