Sinkhole

A powerful cyclone once made one of the world's largest sinkholes completely fill with water.

This gaping hole in the middle of a remote mountain lake looks like a portal to another dimension.

Climb down into the largest sinkhole in Qatar.

Three sinkholes filled with warm, crystal-clear water reached by a horse-driven cart on an old train track through the jungle.

This 50-foot-deep sinkhole created in the 14th century is home to rare plants and fungi.

Two massive and unstable sinkholes are yearning to unite, and their consummation could be catastrophic.

Stories of sightless fish and ghostly cowboys are only a fraction of the legends surrounding this Kansas sinkhole.

A sinkhole and now a swimming hole, too, full of dazzling turquoise water.

A mysterious crater-like pond has a spooky tendency to empty and fill with complete disregard to rainfall patterns.

Impressive sink holes fill this untouched old-growth forest in the Bahamas.

This natural wonder drops 16 stories straight down through rare flora and streaming waterfalls.

This lake in the Cascades lives up to its name, disappearing down a hole every spring.