Fireworks at Clifford's Tower during the Jorvik Viking Festival (© Ian Forsyth/Stringer/Getty Images)

Königstein Fortress, Saxon Switzerland, Germany (© Bildagentur-online/Exss/Alamy)

Young alpine marmot (© Jonas Fichtner-Pflaum/Getty Images)

Ribblehead Viaduct and Ingleborough mountain, North Yorkshire, England (© AWL Images/DanitaDelimont.com)

Golden Bridge, Bà Nà Hills, Da Nang, Vietnam (© Hien Phung Thu/Shutterstock)

Scottish Blackface sheep, Aberdeenshire, Scotland (© Mike Powles/Getty Images)

Alstrom Point, Lake Powell, Utah, United States (© T.M. Schultze/TANDEM Stills + Motion)

Art installation of umbrellas, Borough Market, London, England (© Malcolm P Chapman/Getty Images)

Yungang Grottoes, Datong, Shanxi province, China (© Eric Yang/Getty Images)

Marine iguanas, Galápagos Islands, Ecuador (© helovi/Getty Images)

Lake Tyrrell, Victoria, Australia (© Monica Bertolazzi/Getty Images)

Two Magellanic penguins, Falkland Islands (© Vicki Jauron, Babylon and Beyond Photography/Getty Images)

A kingfisher perched on a branch (© NJphoto/Alamy Stock Photo)

Humpback whale mother and calf, Tonga (© Chase Dekker/Minden Pictures)

Great Blue Hole, Belize (© JamiesOnAMission/Shutterstock)

European river otter, Lelystad, Netherlands (© Ernst Dirksen/Minden Pictures)

Red deer, Canada (© Delbars/Getty Images)

Champaka Sarasi pond near Shivamogga, Karnataka, India (© Amith Nag Photography/Getty Images)

Gateway Arch and St Louis, Missouri, United States (© f11photo/Getty Images)

Mount Fuji, Lake Kawaguchi, Japan (© Twenty47studio/Getty Images)

Group of giant cuttlefish in Spencer Gulf, off Whyalla, South Australia (© Gary Bell/Minden Pictures)

Sandstone hoodoos, Bryce Canyon National Park, Utah, United States (© Stephen Matera/TANDEM Stills + Motion)

Castle Stalker on Loch Laich, Argyll, Scotland (© WLDavies/Getty Images)

Polar bear cub, Churchill, Manitoba, Canada (© Eric Baccega/NPL/Minden Pictures)

Taktsang Palphug Monastery, Bhutan (© Baron Reznik/Getty Images)