Juan Carlos Munoz / Water cascading down Toberia falls, Andoin, Sierra Entzia Natural Park, Alava, Basque Country, Spain, April.

Bruno D'Amicis / Tisisat Falls / Blue Nile Falls along the Blue Nile, south of Bahir Dar, Lake Tana Biosphere Reserve, Ethiopia. December 2013.

Bruno D'Amicis / Tisisat Falls / Blue Nile Falls along the Blue Nile, south of Bahir Dar, Lake Tana Biosphere Reserve, Ethiopia. December 2013.

Juan Carlos Munoz / Aerial view of waterfall on the coastline of Corcovado National Park, Osa Peninsula, Puntarenas Province, Costa Rica. December 2014.

Peter Cairns / Selfoss waterfall in autumn with snow, north Iceland, September 2013.

Juergen Freund / Wangi Falls at night illuminated by moonlight, Litchfield National Park, Northern Territory, Australia. December 2012.

Erlend Haarberg / Meltwater from Engenbreen glacier, Meloy, Nordland, Norway, August.

Alex Hyde / Takob-Akob Falls plunging 38 metres through the rainforest. Southern plateau edge, Maliau Basin, Sabah, Borneo, May 2011.

Floris van Breugel / Salto Grande waterfall with Paine Grande beyond, Torres del Paine National Park, Chile, June 2014.

Hougaard Malan / Berlin falls on a summer afternoon. Panorama route, Mpumalanga, South Africa. March 2013.

Hougaard Malan / Tugela falls surrounded by clouds on a misty morning. Royal Natal National Park, Drakensberg, South Africa. November 2010.

Hougaard Malan / Tugela falls surrounded by clouds on a misty morning. Royal Natal National Park, Drakensberg, South Africa. November 2010.