Couple and woman hiking through the jungle on Saba Island, Netherlands Antilles, West Indies, Caribbean, Central America

Woman hiking through the giant elephant ear plants, Saba Island, Netherlands Antilles, West Indies, Caribbean, Central America

Whalebone Alley, female tourist standing between bow head whale rib bones, Itygran Island (Bering Sea) Russia, Asia. MORE INFO: Whale Bone Alley was discovered by Soviet archaeologists in 1976, but has remained untouched since and little is known of this place. There is a long double line of bowhead whale bones -- jaws and ribs -- running parallel along the shore for hundreds of yards. Many of the bones, especially the enormous jaw bones, are still standing, propped up by lichen-covered rocks. The location is thought to have been used in about 1300 as a ceremonial site, for a men's secret society or feasting site.

Whalebone Alley, female tourist sitting on bowhead whale bone, Itygran Island (Bering Sea) Russia, Asia. MORE INFO: Whale Bone Alley was discovered by Soviet archaeologists in 1976, but has remained untouched since and little is known of this place. There is a long double line of bowhead whale bones -- jaws and ribs -- running parallel along the shore for hundreds of yards. Many of the bones, especially the enormous jaw bones, are still standing, propped up by lichen-covered rocks. The location is thought to have been used in about 1300 as a ceremonial site, for a men's secret society or feasting site.

Tourist Female hiker walking, exploration on Bering Islands (Bering Sea) Russia, Asia

Guests from the Lindblad Expedition ship National Geographic Explorer during snowstorm at Deception Island in Antarctica

Natural history staff from the Lindblad Expedition ship National Geographic Endeavour doing various things in and around the Antarctic Peninsula

Natural history staff from the Lindblad Expedition ship National Geographic Endeavour doing various things in and around the Antarctic Peninsula

Distant hiker on stone staircase at sunset

Rear view of woman hiking in woods

Caucasian boy hiking with dog

Pilgrims walking with hiking stick along a sandy road, Andalusia, Spain

Detail of walking sticks in preparation for a hike through the jungle to the Canopy Walkway, Nyungwe Forest National Park, Western Province, Rwanda, Africa

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

Cross-country skiers during the ascent to Seeberspitz Mountain in the Pflersch Valley above Innerpflersch, 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

Old lady wearing the clothes and Islam veil walking the streets of Goreme in Cappadocia, Turkey, Capadocia, Goreme, Brasil, Asia

Man and woman, couple during Nordic Walking in the mountains, Rittner Horn, South Tyrol, Italy, Europe

During the ascent through Valfredda to Forca Rossa above Pellegrino Pass, Dolomites, Trentino, Italy, Europe

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

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

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

Woman snowshoeing near a mountain hut in the valley Kleinwalser Austria

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

Young couple soaks in the view of the fall colors and the Blue Ridge Parkway from Potato Knob while hiking the Mountains-to-Sea

A Man Looking At Trees While Hiking Along The Appalachian Trail

A Man Hikes Along The Appalachian Trail

TORRES DEL PAINE NATIONAL PARK, PATAGONIA, CHILE, Chile

Man Standing Under The Northern Lights, Near Keno, Yukon, Canada

View taken from behind of a person walking down a mountainside with a spectacular view of the Kusawa Lake below, Yukon, Canada

Two girlfriends sitting in a grass field posing for a self-portrait with a selfie stick and smart phone; Edmonton, Alberta, Canada

Man Standing On A Mountain Top Overlooking The Klondike Valley In Autumn, Yukon, Canada

Family hiking in field of wildflowers

Female hiker standing on rock in stream in forest