Massive sinkholes on a mountain in one of the most remote places in Venezuela.

Intensely colorful calcite pools in Southern China.

Snow-capped peaks, colorful waterfalls and stunning vistas on the edge of the Himalayas.

Stroll through a wonderland of stupendous moss-covered trees.

Fire meets ice at the southernmost volcano on Earth.

This "floating island" plateau sits 7,671 feet above the forest floor.

In the middle of an extremely unforgiving and desolate high desert is the most secret military facility in the world.

The most alien-looking place on Earth.

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

A battle between nature and architecture in the Cambodian jungle.

A naturally beautiful, seemingly bottomless deep blue spring.

A spectacular cave and a beguiling lake.

Bohol's mysterious brown hills.

This dramatic sea spire is home to the world's rarest insect and is part of the lost continent of Zealandia.

The rocks in this arid basin leave trails of movement behind them.

Macabre astrological automaton clock dating to the late 1400s.