The underground sanctuary of a mysterious ancient cult.

Architectureal fantasy quarter of Rome.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Unsurprisingly, Holland is home to one of the most magnificent flower gardens in the world.

These fantastically named natural pools look like something out of a Scottish myth.

Rippling sand dunes frozen in the Arizona rock.

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

A seemingly endless landscape of pure salt stretches far across Bolivia.

There's a mini version of Iguazu Falls hidden in the Balkans, and it's got a rope swing.

A series of waterfalls so massive they straddle the border of Argentina and Brazil.

Holy Hindu shrine in an enormous, monkey-filled limestone cavern.

World's largest cave was only discovered in 1991, and now offers tours to the public.

Unique geological formations in China, featuring some suggestive shapes.

This deceptively salty lake looks like blushing pink lemonade.

An Australian lake whose pink hue defies scientific explanation.

Breathtakingly blue walls shimmer inside the "Glacier Behind the Town."

The glowing blue Nymphaeum of Emperor Tiberius.