Camel caravan, Khongoryn Els dune, Gobi Desert National Park, Omnogov, Mongolia

A group of gauchos riding horses, with the Cuernos del Paine (Horns of Paine) mountains behind, Torres del Paine National Park, Patagonia, Chile, South America

A group of gauchos riding horses, with the Cuernos del Paine (Horns of Paine) mountains behind, Torres del Paine National Park, Patagonia, Chile, South America

A gaucho riding his horse with Cuernos del Paine (Horns of Paine) mountains in the background, Torres del Paine National Park, Patagonian Andes, Patagonia, Chile, South America

Adult female mountain gorilla (Gorilla gorilla beringei) with infant riding on her back, Amahoro A group, Volcanoes National Park, Rwanda, Africa

Tourists on a horse tour in Vinales National Park, UNESCO World Heritage Site, Pinar del Rio Province, Cuba, West Indies, Caribbean, Central America

A cowboy wrangler leads a pack train of horses up the South Kaibab Trail in Grand Canyon National Park, UNESCO World Heritage Site, Arizona, United States of America, North America

Cyclist riding on lane in autumn, Borrowdale, Lake District National Park, UNESCO World Heritage Site, Cumbria, England, United Kingdom, Europe

Riding the bus along the 92 mile-long road into Denali National Park, Alaska, United States of America

A mountain biker descends the trail from The Old Man of Coniston in the Lake District National Park, Cumbria, England, United Kingdom, Europe

Cycling, Yosemite National Park, UNESCO World Heritage Site, California, United States of America, North America

Dromedary ride on slopes of Timanfaya mountain, Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Mountain bikers stop to consider their route around Loughrigg Fell in the Lake District National Park, Cumbria, England, United Kingdom, Europe

Riding the bus in Denali National Park, Alaska, USA

Explorers riding a zodiac, in Seno Almirantazgo, PN Alberto de Agostini, Tierra del Fuego, Patagonia, Chile

Adult bull American Bison buffalo ( Bos bison ) with Brown-headed Cowbird ( Molothrus ater ) on back in prairie landscape at Riding Mountain National Park Manitoba Canada

Adult bull Elk Wapitii ( Cervus elaphus ) trotting in prairie wooded landscape setting at Riding Mountain National Park Manitoba Canada

Horseback rider, Bryce Canyon, Bryce Canyon National Park, Utah, USA

People riding camels in volcanic landscape, Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Two men on mountain bikes riding over rocks, Gooseberry Trail, Zion National Park, Springdale, Utah, USA

Horse riding, Torrey, Capitol Reef National Park, Utah, USA

Cyclists on a road, volcanic landscape at Los Hervideros, Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Tourists riding dromedaries in the Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Mountain bikers in the Rose Valley, Uchisar, Goereme Valley, Cappadocia, Turkey, Western Asia

Mountain biker, Moab, Utah, USA

Tourists riding camels in Montana del Fuego de Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Sign, No Trespassing - National Park, in the back tourists riding dromedaries in the Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Tourists riding camels in Montana del Fuego de Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Tourists riding camels in Montana del Fuego de Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Tourists riding camels in Montana del Fuego de Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Tourists riding dromedaries in the Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Tourists riding camels in Montana del Fuego de Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Tourists riding camels in Montana del Fuego de Timanfaya National Park, Lanzarote, Canary Islands, Spain, Europe

Sheeps with shepherd on horse, grazing on their summer pasture. National Park Besch Tasch in the Talas Alatoo mountain range, Tien Shan or Heavenly Mountains. Asia, Central Asia, Kyrgyzstan

Sheeps with shepherd on horse, grazing on their summer pasture. National Park Besch Tasch in the Talas Alatoo mountain range, Tien Shan or Heavenly Mountains. Asia, Central Asia, Kyrgyzstan

Sheeps with shepherd on horse, grazing on their summer pasture. National Park Besch Tasch in the Talas Alatoo mountain range, Tien Shan or Heavenly Mountains. Asia, Central Asia, Kyrgyzstan

Female hiker waits for pack horses to pass on the South Kaibab Trail in Grand Canyon National Park north of Williams, Arizona May 2011. The South Kaibab Trail starts on the south rim of the Colorado Plateau and follows a ridge out to Skeleton Point allowing for 360-degree views of the canyon then down to the Colorado River. At the Colorado River the trail connects with the North Kaibab trail as part of the Arizona Trail system, that crosses the state of Arizona from Mexico to Utah.

A Pair Of Mountain Bikers Riding On The Mercantour National Park, France

A Mountain Biker In The Backcountry Of Mercantour National Park, France

A man fat biking on the Nabesna Road in Wrangell-St. Elias National Park and Preserve on a cloudy summer day in South-central Alaska, Alaska, United States of America

Four Horses Standing In A Row At A Fence Along The Edge Of A Pasture, Riding Mountain National Park, Manitoba, Canada

Young Woman In Foreground, Young Man In Background, On Sailboat, Clear Lake, Riding Mountain National Park, Manitoba, Canada

A helicopter tour provides stunning views over the Mount Cook glacier and surrounding mountaintops, Mount Cook National Park; Canterbury, New Zealand

A man fat biking on the Nabesna Road in Wrangell-St. Elias National Park and Preserve on a cloudy summer day in South-central Alaska, Alaska, United States of America

A man fat biking on the Nabesna Road in Wrangell-St. Elias National Park and Preserve on a cloudy summer day in South-central Alaska, Alaska, United States of America

Muskoka chair on dock with autumn coloured foliage reflected in the tranquil lake water of Clear Lake, Riding Mountain National Park, Manitoba, Canada

Woman On Public Dock Clear Lake, Canada, Manitoba, Riding Mountain National Park

An American Bison (Bison Bison) Stands In A Grass Field In Riding Mountain National Park, Manitoba, Canada

A Wooden Dock Leading Out To A Misty Tranquil Lake In Riding Mountain National Park, Wasagaming, Manitoba, Canada

Ominik Marsh Boardwalk, Riding Mountain National Park, Manitoba, Canada

Whirlpool River, Riding Mountain National Park, Manitoba, Canada