Ernie Janes / Board walk in Donana National Park, Almonte, Spain, October 2017.

Richard Du Toit / Boardwalk through marsh, Garden Route National Park, Western Cape, South Africa

Ernie Janes / Brown fur seal (Arctocephalus pusillus) hauled out on board walk in Cape Cross seal colony, Namibia

Ingo Arndt / Wooden boardwalk in reed beds shortly before sunrise, Federsee, Germany, October 2015.

Merryn Thomas / Hiker walking towards Valle Frances, on middle stage of W Trek. Torres del Paine National Park, Patagonia, Chile. January 2014.

Kirkendall-Spring / Noris Geyser Basin, Yellowstone National Park, Wyoming, USA. September 2015.

Jean E. Roche / Greater flamingos (Phoenicopterus roseus) flock, near Pont de Gau Ornithological Park, Camargue, France, February.

Jean E. Roche / Red fox (Vulpes vulpes) on board walk in marsh, Camargue, France, September.

Jean E. Roche / Red fox (Vulpes vulpes) sitting on board walk in marsh, Camargue, France, September.

Chris Mattison / Raised board walk over Dersingham Bog National Nature Reserve, Norfolk, UK November

Chris & Monique Fallows / Boardwalk and seating area over lake, Okavango Delta, Botswana, January.

Sean Crane / Wooden path winding through rainforest, Cradle Mountain-Lake Saint Clair National Park, Tasmania, Australia