Arctic fox sleeping (© Chansak Joe/Getty Images)

Aerial view of Venice, Italy (© Clement Leonard/Getty Images)

Staubbach Falls at Lauterbrunnen, Canton of Bern, Switzerland (© pongnathee kluaythong/Getty Images)

Kings Mountain, Chugach Mountains, Alaska, United States (© Chris Moore - Exploring Light Photography/TANDEM Stills + Motion)

A herd of impalas, Londolozi Game Reserve, South Africa (© Mint Images/Getty Images)

Nuuk, Greenland (© nevereverro/Getty Images)

Turret Arch framed by North Window in Arches National Park, Utah, United States (© Jim Patterson/TANDEM Stills + Motion)

Giant redwood trees in Muir Woods National Monument, California, USA (© photo by canderson/Getty Images)

The Matterhorn reflected in Lake Stellisee, Zermatt, Switzerland (© Andy Trowbridge/naturepl.com)

Blue walls of Chefchaouen, Morocco (© AnetteAndersen/Getty Images)

Eurasian otter and pup, Estonia (© Sven Zacek/naturepl.com)

Vale of Clwyd, Wales (© Valerie Blencowe/Getty Images)

The staircase of the Fortress of Palamidi, Nafplio, Greece (© George Pachantouris/Getty Images)

The fishing village of Reine, Norway (© Roberto Moiola/Cavan Images/SuperStock)

Leopard at Etosha National Park, Namibia (© Norbert Achtelik/Cavan Images)

Basilica of San Francesco di Paola, Naples, Italy (© javarman3/Getty Images)

Scots pine forest, Ashdown Forest, England (© James Warwick/The Image Bank/Getty Images)

Frozen Abraham Lake, Alberta, Canada (© Luis F Arevalo/Getty Images)

Gentoo penguin, Petermann Island, Antarctica (© Paul Souders/DanitaDelimont.com/Alamy)

Eurasian red squirrel (© Galina Jacyna/Getty Images)

Karlovy Vary, Bohemia, Czechia (© Henryk Sadura/Getty Images)

Sheep grazing in snow, Iceland (© Christophe Lehenaff/Getty Images)

Red kite in snow (© Carl Mckie/500px/Getty Images)

Northumberland, England (© Design Pics/John Short/Getty Images)

Neuschwanstein Castle, Bavaria, Germany (© www.fredconcha.com @ All Rights Reserved/Getty Images)

Dalmatian pelicans, Lake Kerkini, Greece (© Guy Edwardes/naturepl.com)

Whanganui National Park, Retaruke, New Zealand (© Matthew Micah Wright/Getty Images)

The eight-story open atrium of Milwaukee City Hall, Wisconsin, USA (© lavin photography/Getty Images)

St Michael's Mount in Marazion, Cornwall, England (© Baxter Bradford/robertharding/Getty Images)

Plains zebras, Etosha National Park, Namibia (© Mogens Trolle/Shutterstock)