Pack horses laden with trekking equipment cross the Konze La on the Hidden Valleys trek, Ladakh, India, Asia

Pack ponies carrying trekking equipment cross the Laurebina La from Langtang and descend into cloud towards Helambu, Nepal, Himalayas, Asia

Young woman faces blizzard while hiking in snowy day at Pe?alara, highest mountain peak in the mountain range of Guadarrama, Spain

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

Hiking woman, National Park Hohe Tauern, Tyrol, Austria

Camp at Cerro Rojo, Salar de Surire, Reserva Nacional de las Vicunas, Lauca National Park, Chile

Sherpa porter with heavy load, Sagarmatha National Park, Khumbu Himal, Nepal

Sherpa porters with heavy load, Sagarmatha National Park, Khumbu Himal, Nepal

Tourist crossing the via ferrata trail with equipment in the dolomites. Dolomites, Italy, Dolomites, Italy, Europe

2 men with trekking equipment in rocky landscape, fog, rain, West Greenland, Greenland, North America

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