Tim Fitzharris / The Mittens and Merrick Butte at sunrise, Monument Valley, Arizona

Tim Fitzharris / East and West Mittens, buttes with rippled sand, Monument Valley, Arizona

Gavin Hellier / The 'Mittens' at sunset Monument Valley Navajo Tribal Park, Arizona, USA

Tim Fitzharris / Sand dunes and the Mittens, Monument Valley Navajo Tribal Park, Arizona

Ingo Arndt / East and West Mittens, Monument Valley, Navajo Tribal Park, Arizona, USA, September 2010

Ingo Arndt / East and West Mittens, Monument Valley, Navajo Tribal Park, Arizona, USA, September 2010

Ingo Arndt / The Mittens and Merrick Butte, Monument Valley, Navajo Tribal Park, Arizona, USA, September 2010

Ingo Arndt / East and West Mittens, Monument Valley, Navajo Tribal Park, Arizona, USA, September 2010

Bryan and Cherry Alexander / Close up of the sleeves of a Nenets man's reindeer skin Malitsa (coat) with reindeer skin mittens attached to it. Yamal, Western Siberia, Russia

Hiroya Minakuchi / Mittens in desert, Monument Valley Navajo Tribal Park, Arizona

Hiroya Minakuchi / Mittens in desert, Monument Valley Navajo Tribal Park, Arizona

Hiroya Minakuchi / Mittens in desert, Monument Valley Navajo Tribal Park, Arizona

Hiroya Minakuchi / Mittens being illuminated by light, Monument Valley Navajo Tribal Park, Arizona

Diane McAllister / Japanese Macaque (Macaca fuscata) foraging for food in deep snow, front paws covered in snow, Jigokudani, Japan, January

Tim Fitzharris / Mittens, North Window, Monument Valley, Arizona

Tim Fitzharris / Moon over mittens, Monument Valley, Arizona

Tom Vezo / East and West Mittens, Monument Valley, Utah

Tom Vezo / Mittens at sunrise, Monument Valley Navajo Tribal Park, Arizona

Bryan and Cherry Alexander / Nenets girl, warmly dressed in reindeer skin clothing, carrying snow to melt for water. Yamal, Northwest Siberia, Russia, February 2007. Editorial use only.

Bryan and Cherry Alexander / Man demonstrating the layers he wears to keep warm (underwear, mid layers, outer layer, jacket & mittens) Antarctica, January 2006. Digital composite.

Steven Kazlowski / West and East Mitten buttes silhouetted at sunset, Monument Valley, Navajo Tribal Park, Arizona, USA. February 2009.

Steven Kazlowski / West and East Mitten buttes silhouetted at sunset, Monument Valley, Navajo Tribal Park, Arizona, USA. February 2009.

Staffan Widstrand / Traditional inuit kayak with polar bearskin mittens and seat cover, Qaanaaq, NW Greenland, 1996.

Philippe Clement / The Mittens at dawn, Monument Valley Navajo Tribal Park, Arizona, USA May 2007

Philippe Clement / The Mittens and clouds forming over the Monument Valley Navajo Tribal Park, Arizona, USA May 2007

Philippe Clement / The Mittens and clouds forming over the Monument Valley Navajo Tribal Park, Arizona, USA May 2007

Philippe Clement / The Mittens, Monument Valley Navajo Tribal Park, Arizona, USA May 2007

Philippe Clement / The Mittens and clouds forming over the Monument Valley Navajo Tribal Park, Arizona, USA May 2007

Tim Fitzharris / East and West Mittens, buttes at sunrise with full moon, Monument Valley, Arizona

Tim Fitzharris / East and West Mittens, buttes at sunrise, Monument Valley, Arizona

Tim Fitzharris / East and West Mittens, buttes at sunrise, Monument Valley, Arizona

Gavin Hellier / Panoramic view of The Mittens at sunset, Monument Valley Navajo Tribal Park, Arizona, USA

Tim Fitzharris / The east and west Mittens surrounded by rippled sand, Monument Valley Navajo Tribal Park, Arizona

Gavin Hellier / The 'Mittens' in winter with snow in Monument Valley Navajo Tribal Park, Arizona, USA

Gavin Hellier / The 'Mittens', Monument Valley Navajo Tribal Park, Arizona, USA

Gavin Hellier / The 'Mittens' in winter with snow, Monument Valley Navajo Tribal Park, Arizona, USA

Gavin Hellier / The 'Mittens', Monument Valley Navajo Tribal Park, Arizona, USA

Gavin Hellier / Panoramic view of The Mittens in winter, Monument Valley Navajo Tribal Park, Arizona, USA

Gavin Hellier / Panoramic view of The Mittens, Monument Valley Navajo Tribal Park, Arizona, USA

Gavin Hellier / Panoramic view of The Mittens, Monument Valley Navajo Tribal Park, Arizona, USA

Gavin Hellier / Panoramic view of The Mittens, Monument Valley Navajo Tribal Park, Arizona, USA

Gavin Hellier / Panoramic view of The Mittens in winter, Monument Valley Navajo Tribal Park, Arizona, USA

Hiroya Minakuchi / Mittens, Monument Valley, Utah

Tim Fitzharris / The Mittens at sunset, Monument Valley, Arizona

Tim Fitzharris / The Mittens at sunset, Monument Valley, Arizona

Hiroya Minakuchi / Mittens in desert, Monument Valley Navajo Tribal Park, Arizona

Hiroya Minakuchi / Mittens being illuminated by light, Monument Valley Navajo Tribal Park, Arizona

Hiroya Minakuchi / Mittens being illuminated by light, Monument Valley Navajo Tribal Park, Arizona

Tim Fitzharris / Sandstorm enshrouding mittens, Monument Valley, Arizona

Yva Momatiuk & John Eastcott / Cirrus and cumulus clouds over Mittens, a group of sandstone mesas, Monument Valley Navajo Tribal Park, Arizona

Enrique Lopez-Tapia / View of the iconic sandstone butte named The 'Mittens', at sunset, Monument Valley, Navajo Tribal Park. Arizona, USA.

Enrique Lopez-Tapia / View of the iconic sandstone butte named The 'Mittens', at sunset, Monument Valley, Navajo Tribal Park. Arizona, USA.

Enrique Lopez-Tapia / View of the iconic sandstone buttes named The 'Mittens', at sunset, Monument Valley, Navajo Tribal Park. Arizona, USA.

Enrique Lopez-Tapia / View of the iconic sandstone buttes named The 'Mittens', at sunset, Monument Valley, Navajo Tribal Park. Arizona, USA.

Enrique Lopez-Tapia / View of the iconic sandstone buttes named The 'Mittens', at sunset, Monument Valley, Navajo Tribal Park. Arizona, USA.

Enrique Lopez-Tapia / View of the road into Monument Valley with the huge sandstone buttes, 'The Mittens and Merrick butte on the background, Monument Valley, Arizona, USA.

Bryan and Cherry Alexander / Otto Simigak with a mug of tea during a break on a hunting trip in light snow. Siorapaluk, Northwest Greenland.1977.