Mother Nature outdoes herself with this stunningly beautiful set of caves carved into marble.

Iceland's largest lagoon is home to stunning multi-colored icebergs.

An emerald-green grotto just a short trip from Austin.

Geothermal waterfalls in Tuscany.

Stunning wetlands ablaze with pink lotus flowers.

Enormous lake at the bottom of a unique cave system.

Medicinal spa created with the discharge from a geothermal energy plant.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

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

Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.

The glowing blue Nymphaeum of Emperor Tiberius.

Rising from the sea like a stone monster.

A massive underwater sinkhole made famous by Jacques Cousteau.

Trick water gardens from 1619 featuring a 200 piece mechanical theater powered by water.

An ethereal glowing blue ocean cave in Croatia.

Roman ruins top white travertine terraces formed by ancient hot springs.