View of snow covered trees and Courmayeur from Dolonne in winter, Courmayeur, Aosta Valley, Italian Alps, Italy

View of snow covered trees, mountains and cable car from Dolonne to Plan Checrouit from Courmayeur, Courmayeur, Aosta Valley, Italian Alps, Italy

View of snow covered mountains, rooftops and Church of Saint Pantalon in Courmayeur in winter, Courmayeur, Aosta Valley, Italian Alps, Italy

View of wooden roof on snow covered house and church in Entreves in winter, Entreves, Aosta Valley, Italian Alps, Italy

Dramatic purple sunset above snowy rugged summits of Los Cumbres Verdes, part of the Sierra Nevada, viewed from Granada, Andalucia, Spain

Beautiful hiking path on steep rocky and grassy slopes in the Italian Alps, Colle del Turlo, Vercelli, Piedmont, Italy, Europe

Panoramic view of the snowy Sierra Nevada with Alcazaba, Mulhacen and Pico de Veleta, viewed from Guejar Sierra, Sierra Nevada, Andalusia, Spain, Europe

French Alps in winter, famous ski station, Saint Gervais Mont-Blanc village, Saint Gervais, Haute Savoie, France, Europe

French Alps in winter, gondola lift at famous ski station, Saint Gervais Mont-Blanc village, Saint Gervais, Haute Savoie, France, Europe

Low clouds and mist around Grandes Jorasses and Mont Blanc while hikers proceed on Lac De Cheserys, Haute Savoie, French Alps, France, Europe

One man looking at the alpine lake of Montespluga standing on rocks, Madesimo, Valle Spluga, Valtellina, Lombardy, Italy, Europe

Low clouds and mist around Grandes Jorasses and Mont Blanc while hikers proceed on Lac De Cheserys, Haute Savoie, French Alps, France, Europe

Mount Ngauruhoe, Tongariro Alpine Crossing, Tongariro National Park, UNESCO World Heritage Site, North Island, New Zealand, Pacific

Caucasian woman hiking on remote hillside

Mari backpacker walking in mountain valley

Caucasian grandfather and granddaughter hiking on mountain

Woman hiking on mountain in winter

Man hiking on mountain in winter

Caucasian mother and son hiking on remote hillside

Hikers exploring rock cave

Mari backpacker walking in remote stream

Backpackers crossing remote stream

Aerial view of trees in landscape

Camping tent in snowy landscape

Mari backpacker walking on mountain path

Backpackers walking on rural path

Hikers standing at entrance of cave

Distant people running on beach

Caucasian mother and son sitting on remote hilltop

Mari backpacker walking on dirt path

Caucasian mother and son hiking on remote hillside

Backpack in mountain field

Caucasian mother and son hiking on remote hillside

Mari backpacker walking on mountain path

Mari hiker admiring remote mountains

Mari backpacker walking in remote field

Mari hiker admiring mountain valley

Distant view of hikers walking on remote hillside

Mari backpacker standing in mountain field

Kevin Jorgeson climbing "Fantasia" at Lover's Leap, a popular granite climbing destination near Lake Tahoe in California's Sierra Nevada mountains. The cliff is known for its distinct horizontal quartz dikes which make interesting climbing. This route is considered a risky mental test piece because of its lack of good cracks for protection. It was first climbed in 1973 by Royal Robbins and Ken Wilson.

A camper on the coastal plain, 1002 Area, of the Arctic National Wildlife Refuge looks back towards the mountains, Alaska.

A climber holds up his ice axe while walking on a snow covered alpine ridge.

Rob Raker ascends a vertical pitch of glacial ice high on the Cassin Ridge route of Denali (Mt. McKinley), Alaska in May 1990. This pitch is the technical crux of the route which ascends the South Face to the summit at 20,320 feet, the highest point in North America. (Photo by Kevin Steele, Aurora)

Katy Holm sorts gear at the base Cerro Pollone in Argentine Patagonia. January 2005

A man swings his ice tools as he climbs out of a moulin on a day trip with St. Elias Alpine Guides to the Root Glacier in Wrangell-St. Elias National Park, Alaska.

A woman swings her ice tools as she prepares to climb out of a moulin on a day trip with St. Elias Alpine Guides to the Root Glacier in Wrangell-St. Elias National Park, Alaska.

Two men backpacking in an alpine meadow with a lake in Eastern Sierra Nevada mountains, California.

Four skiers alpine touring in Colorado.

Climber in shorts with trekking poles summits Mount Rainier, Washington.

Hikers backpacking on mountain, Everest, Khumbu region, Nepal, Everest, Khumbu region, Nepal

Man sitting in base camp tent, Everest, Khumbu glacier, Nepal, Everest, Khumbu glacier, Nepal