Guy Edwardes / Sea Stacks at Mangurstadh, Aird Feinis, Isle of Lewis, Outer Hebrides, Scotland, UK. March 2015.

Ingo Arndt / Twelve Apostles rock formations Port Campell NP, New South Wales, Australia

Kirkendall-Spring / Trees and sea stacks silhouetted in fog at Point of the Arches in Olympic National Park. Washington, USA, August 2012.

Peter Cairns / Reynisdrangar sea stacks at dusk, Vik, Iceland

Erlend Haarberg / Londrangar sea stacks, Snaefellsnes peninsula, Iceland, February 2011

Erlend Haarberg / Northern fulmar (Fulmarus glacialis) in flight in snow storm, Iceland, April

Erlend Haarberg / Northern gannet (Morus bassanus) colony on a sea stack and seabird cliff, Langanes peninsula, Iceland, July

Brent Stephenson / Australasian Gannet (Morus serrator) breeding colony above sea stacks. Muriwai, Auckland, New Zealand, November.

Inaki Relanzon / Cliffs and sea-stacks on the coast of "El Hierro" Island. Canary Islands, February 2011.

Matthew Maran / A man looking out to sea by coastal rock stacks. The West Coast Trail, Pacific Rim National Park, Vancouver Island, Canada, September 2010. Model released.

Eric Baccega / Flowerpot sea stacks with outgoing tide at Hopewell Rocks. The world's highest tides. Bay of Fundy, New Brunswick, Canada, September 2010

Guy Edwardes / Reynisdrangur stacks and black sand beach Vik i Myrdal at night, Iceland, June 2009