Spectacular limestone outcrops, forests and waterfalls of Zhangjiajie Forest Park in the Wulingyuan Scenic Area, Hunan Province, China

Limestone waterfall, Semuc Champey, Guatemala, Central America

Steps of limestone strata make a waterfall on the Rio Arazas, upper Ordesa Valley, Ordesa National Park, Pyrenees, Aragon, Spain, Europe

Waterfall on Rio Bellos river in the limestone Anisclo Canyon, Ordesa National Park, Anisclo, Pyrenees, Aragon, Spain, Europe

Weeping Wall, water freezing over a limestone cliff, Banff National Park, UNESCO World Heritage Site, Rocky Mountains, Alberta, Canada, North America

Limestone formations and waterfall at Buttertubs on the Pass from Wensleydale to Swaldale, Yorkshire Dales, Yorkshire, England, United Kingdom, Europe

Small waterfall in spectacular limestone outcrops and forested valleys of Zhangjiajie Forest Park in Wulingyuan Scenic Area, UNESCO World Heritage Site, Hunan, China, Asia

The Underworld - Photographs from a very famous European cave called The Gouffre Berger, in France

A cave explorer reaches the top of a waterfall underground in New Britain

Tomb Submerged In A Travertine Pool In Hierapolis At Sunset, Pamukkale, Turkey

Hot Springs And Travertines, Terraces Of Carbonate Minerals Left By The Flowing Water, Pamukkale, Turkey

Tomb Submerged In A Travertine Pool In Hierapolis, Pamukkale, Turkey

Cascade du Chapeau de gendarme, Septmoncel-les-Molunes, Jura, France