Mountaineers and climbers, Mont Blanc range, French Alps, France, Europe

Hikers descend from Pen-Y-Fan summit in The Brecon Beacons National Park, Powys, Wales, United Kingdom, Europe

Lake Morskie Oko (Eye of the Sea), Zakopane, Carpathian Mountains, Poland, Europe

Trekking in the Kagmara Valley with the first glimpse of Lhashama in the distance, Dolpa Region, Himalayas, Nepal, Asia

Hiker on cliffs looks towards lake Sorvagsvatn, Vagar Island, Faroe Islands, Denmark, Europe

A female mountaineer crossing the snow fields in winter in the Cairngorm National Park, Scotland, United Kingdom, Europe

Female winter walker descending a fresh snowy slope in the Cairngorm National Park, Scotland, United Kingdom, Europe

Hiker in winter, Motette, Umbria, Italy, Europe

A trekker makes her way to Everest Base Camp, Khumbu Region, Himalayas, Nepal, Asia

Hiker proceeds toward the group Forcella De Furcia at sunrise, Funes Valley, South Tyrol, Dolomites, Italy, Europe

Climbing expedition on Mount McKinley, 6194m, Denali National Park, Alaska, United States of America, North America

Walker looking to Crib Goch and the Llanberis Pass at dawn in winter, Snowdonia National Park, Eryri, North Wales, United Kingdom, Europe

Climbing expedition on Mount McKinley, 6194m, Denali National Park, Alaska, United States of America, North America

Climbing Pacaya volcano, with Fuego Volcano in distance, Antigua, Guatemala, Central America

Walker looking out over Mount Snowdon (Yr Wyddfa), Y Lliwedd and Llyn Llydaw in winter, Snowdon Horseshoe, Cwm Dyli, Eryri, Snowdonia National Park, North Wales, United Kingdom, Europe

Climbing expedition on Mount McKinley, 6194m, Denali National Park, Alaska, United States of America, North America

Walker looking out over Mount Snowdon (Yr Wyddfa), Y Lliwedd and Llyn Llydaw in winter, Snowdon Horseshoe, Cwm Dyli, Eryri, Snowdonia National Park, North Wales, United Kingdom, Europe

Climbing Pacaya volcano, with Fuego Volcano in distance Antigua, Guatemala, Central America

Totem Pole and Yei Bi Chei, Monument Valley, Arizona, United States of America, North America

Mother and sons look at the signpost of hiking trails, Spluga Pass, Chiavenna Valley, Spluga Valley, Lombardy, Italy, Europe

Mother and sons look at the signpost of hiking trails, Spluga Pass, Chiavenna Valley, Spluga Valley, Lombardy, Italy, Europe

Women on their way up Mount Kilimanjaro, UNESCO World Heritage Site, Tanzania, East Africa, Africa

Visitor sign along the Kumano Kodo ancient pilgrimage route near Hongu, Honshu, Japan, Asia

Woman hiking Choquequirao, Peru, South America

Woman hiking Choquequirao, Peru, South America

Snowshoes on a snowy path, Livigno, Valtellina, Lombardy, Italy, Europe

Walker in Snowdonia National Park, Gwynedd, Wales, United Kingdom, Europe

A climber walks towards advanced base camp at 5800 metres on Mera Peak, 6420 metres, a popular trekking peak in the Khumbu region, with Mount Everest beyond, Nepal Himalaya, Nepal, Asia

Mountain hikers in summer in the French Alps, Haute-Savoie, France, Europe

Woman hiking Choquequirao, Peru, South America

Hiking signage along footpath to Rifugio Zsigmondy Comici hut, Val Fiscalina, Sesto/Sexten Dolomites, South Tyrol, Italy, Europe

A trekker heads up into the wilderness of the highest part of the Ecrins Massif in deep winter snow, above the village of Pelvoux, near Briancon, western Alps, Hautes Alpes, south west France, Europe

Hiking Choquequirao, Peru, South America

Woman enjoying the hike towards rifugio Pian di Cengia (Buellelejoch) hut in summer, Sesto Dolomites, South Tyrol, Italy, Europe

Hiker on the trail to Lej Lagrev, St. Moritz, Upper Engadine, Canton of Graubunden, Switzerland, Europe

Hiker walking along a trail surrounded by spring flowers near Cima della Rosetta in the Orobie Alps, Lombardy, Italy, Europe

Old man walking through the Pueblo Indian Ruins in Bandelier National Monument, New Mexico, United States of America, North America

Hikers walking on the Adolf Munkel trail at foot of the Odle, Val di Funes, South Tyrol, Dolomites, Italy, Europe

Hiker standing on top of hill with Vidareidi village and Malinsfjall mountain on background, Vidoy Island, Faroe Islands, Denmark, Europe

Yellow Hotel Sign on rocks in front of mountain slopes, Langtang Valley trek, Himalayas, Nepal, Asia

Rear view of two young hikers admiring the Odle from the famous Adolf Munkel trail, Val di Funes, South Tyrol, Dolomites, Italy, Europe

Man with hiking poles walking in the snow with majestic Orobie Alps in the background, Alpe Rogneda, Rhaetian Alps, Lombardy, Italy, Europe

Rear view of hiker woman walking on path to majestic Croda Dei Toni mountain, Sesto Dolomites, South Tyrol, Italy, Europe

Rear view of mother with male child trekking around the Sassolungo group, Dolomites, Trentino-Alto Adige, Italy, Europe

Hiker woman walking on snowy mountain ridge on path to Rifugio Locatelli hut, Sesto Dolomites, South Tyrol, Italy, Europe

Backpacker woman with hiking poles enjoying the view to Croda Dei Toni from path, Sesto Dolomites, South Tyrol, Italy, Europe

Hiker woman with dog walking on path to the majestic mountain Croda dei Toni in summer, Sesto Dolomites, South Tyrol, Italy, Europe

Hiker on a mountain trail, Barre des Ecrins, Ecrins National Park, French Dauphine Alps, Haute Alpes, France, Europe

Natural Park Puez-Odle, Val di Funes, Bolzano district, Sudtirol (South Tyrol), Italy, Europe

Silhouette of woman on path with Croda Dei Toni mountain in the background, Val Fiscalina, Sesto Dolomites, South Tyrol, Italy, Europe

Views from the Skyline Trail of Mount Rainier National Park, Washington State, United States of America, North America

Cute male child with hiking poles walking on trail around the Sassolungo group, Dolomites, Trentino-Alto Adige, Italy, Europe

A hiker looking west from a cliff near Zuni Abyss at Grand Canyon, Zuni Point in the background just right of center, Grand Canyon National Park, UNESCO World Heritage Site, Arizona, United States of America, North America

A hiker looks at Lake Pirola from above at sunrise, Chiareggio valley, Valmalenco, Valtellina, Lombardy, Italy, Europe

Trekkers on Arcuentu mountain, Sardinia, Italy, Europe

Hiker woman walking on path to majestic Croda Dei Toni mountain at dawn, Val Fiscalina, Sesto Dolomites, South Tyrol, Italy, Europe

Hiker woman with backpack walking on path to Croda Dei Toni at sunrise, Val Fiscalina, Sesto Dolomites, South Tyrol, Italy, Europe

Trekkers on Arcuentu mountain, Sardinia, Italy, Europe

Walker on the PYG track backed by Cwm Dyli, Llyn Llydaw and Y Lliwedd in winter, Snowdonia National Park, Eryri, North Wales, United Kingdom, Europe

Mother with two little sons walking on path in green meadows towards Rifugio Sassopiatto, Dolomites, Trentino-Alto Adige, Italy, Europe

A hiker standing on a rock island at Pinal Point Grand Canyon, Grand Canyon National Park, UNESCO World Heritage Site, Arizona, United States of America, North America

A hiker watching the sun go down west of Moran Point at Grand Canyon, Grand Canyon National Park, UNESCO World Heritage Site, Arizona, United States of America, North America

Hiker contemplating the landscape that can be seen from the Cima della Rosetta in the Orobie Alps in the spring, Lombardy, Italy, Europe

Walker looking to Mount Snowdon (Yr Wyddfa) in winter, Snowdonia National Park, Eryri, North Wales, United Kingdom, Europe

Hiker in a mountain cave in autumn season in Stelvio National Park in Brescia Province, Lombardy, Italy, Europe

Mountain trekker in autumn season in Stelvio National Park in Brescia Province, Lombardy, Italy, Europe.

Hikers admiring the mountains in autumn season in Stelvio National Park in Brescia Province, Lombardy, Italy, Europe

Women fell walkers in heavy snow on Quinag, Sutherland, Scottish Highlands, Scotland, United Kingdom, Europe

Women fell walkers in heavy snow on Quinag in Scotland, United Kingdom, Europe

Rear view of woman hiking in woods

Distant hiker on stone staircase at sunset

Smiling mixed race woman hiking with walking sticks

Portrait of smiling women hiking

Caucasian grandfather and granddaughter hiking on mountain

Smiling hiking women resting on a tree

Mixed race woman hiking with walking sticks

Caucasian man walking in forest

Tourists walking in the dunes, UNESCO World Biosphere Reserve, Slowinski National Park, Polish Baltic Sea coast, Leba, Pomeranian, Poland

Ascent of Piz Boe Mountain on the Piazzetta Climbing Route, Dolomites, Alto Adige, Italy, Europe

Hiker crossing a wooden bridge above a mountain brook, National Park Hohe Tauern, Tyrol, Austria

Family hiking on Lake Kaltern, province of Bolzano-Bozen, Italy, Europe

Hiking woman, National Park Hohe Tauern, Tyrol, Austria

Snow shoe hikers during ascent to Mt Hoertlahner above Durnholz, Sarntal valley, Mt Hoertlahner at back, South Tyrol, Italy, Europe

Ascent of Piz Boe Mountain on the Piazzetta Climbing Route, Dolomites, Alto Adige, Italy, Europe

Female hiker walking on a snow slab, on the Laugavegur hiking trail, Hrafntinnusker-Álftavatn, Fjallabak Nature Reserve, Highlands of Iceland, Iceland, Europe

View from Herrensteig Mountain over the Kofelwiesen alpine pastures in Villnoess Valley, Dolomites, Alto Adige, Italy, Europe

Mountain climber ascending Hochfeiler Mountain, Pfitschertal Valley, in front of the Dolomites, Alto Adige, Italy, Europe

Roped party on glaciers Styggebreen, climb to Galdhøppigen, 2469 m, Oppland, Norway, Europe

Female hiker walking on a snow slab, on the Laugavegur hiking trail, Hrafntinnusker-Álftavatn, Fjallabak Nature Reserve, Highlands of Iceland, Iceland, Europe

Hikers climbing Mt Marmolata, fixed rope route on west ridge, Dolomites mountain range, Italy, Europe

Mountain climber passing through Pfitschertal Valley while ascending Hochfeiler Mountain, Alto Adige, Italy, Europe

Hiker crossing a wooden bridge above a mountain brook, National Park Hohe Tauern, Tyrol, Austria

Hiker on Hausberg Mountain, Hartkaiser, view towards the Wilder Kaiser Mountains, Tyrol, Austria, Europe

Guide post on the Rennsteig ridge walk, Grenzadler, near Oberhof, Thuringian Forest, Thuringia, Germany, Europe

Hikers walk on wooden planks between Alesjaure and Tjäktja, Kungsleden trail, Lapland, Sweden

Hiking in the mountains of Indonesia.

Julia Lohfink and Jochen Reiser hiking in the mountains of Appenzellerland, Switzerland.

Hikers descend into Surprise Valley to access the lower canyon through a break in the 400-foot-tall Redwall on the Thunder River Trail in the Grand Canyon outside of Fredonia, Arizona November 2011. The 21.4-mile loop starts at the Bill Hall trailhead on the North Rim and descends 2000-feet in 2.5-miles through Coconino Sandstone to the level Esplanada then descends further into the lower canyon to access Thunder River, Tapeats Creek and Deer Creek.

Hikers on the sandstone Esplanade of the Thunder River Trail below the North Rim of the Grand Canyon outside Fredonia, Arizona November 2011. The 21.4-mile loop descends 2000-feet in 2.5-miles through Coconino Sandstone from the Bill Hall trailhead to connect the Thunder River and Deer Creeks trails. Hikers descend into the lower canyon through a break in the 400-foot-tall Redwall to access Surprise Valley, Deer Creek, Tapeats Creek via Thunder River and even the Colorado River.

Mountain ranger Brian Scheele on this way to Windy Corner on Mount McKinley, also know as Denali, in Alaska. He is pulling a sled, that together with his heavy backpack is containing all the gear like tents, clothing and food. Every climbing season High Mountain Rangers of the Denali National Park Service are called to help climbers in need. If possible the patient is brought down to Basecamp on foot, only in life threatening conditions a helicopter is called to evacuate the patient to a hospital in Anchorage. Mount McKinley, native name Denali, is the highest mountain peak in North America, with a summit elevation of 20,321 feet (6,194 m) above sea level. At some 18,000 feet (5,500 m), the base-to-peak rise is considered the largest of any mountain situated entirely above sea level. Measured by topographic prominence, it is the third most prominent peak after Mount Everest and Aconcagua. Located in the Alaska Range in the interior of the U.S. state of Alaska, McKinley is the centerpiece of Denali National Park and Preserve.