Walrus pair at sea in Svalbard, Norway (© Mark Smith/Getty Images)

Turkey tail mushroom, Brevard, North Carolina (© Bill Gozansky/Alamy)

Allen's hummingbird, Santa Cruz, California (© mallardg500/Getty Images)

Aerial view of Manhattan, New York City (© Wojtek Zagorski/Getty Images)

Construction workers on scaffolding (© Bits and Splits/Shutterstock)

Mount Segla, Senja Island, Troms og Finnmark, Norway (© imageBROKER/Moritz Wolf/Getty Images)

Old Venetian harbor, Rethymno, Crete Island, Greece (© Gatsi/Getty Images)

Camels in the desert, United Arab Emirates (© Amazing Aerial Premium/Shutterstock)

The Circus townhouses in Bath, Somerset, England (© Gavin Hellier/Getty Images)

Wat Chaiwatthanaram temple, Ayutthaya Historical Park, Thailand (© Weerasak Saeku/Getty Images)

Brooklyn Bridge with the 'Tribute in Light' installation for 9/11, New York (© ANDREY DENISYUK/Getty Images)

North Sea at sunset, Norddorf, Amrum Island, Germany (© Frederick Doerschem/Getty Images)

Temples on Hemakuta Hill, Hampi, Karnataka, India (© Images of india/Alamy)

Przewalski's horses, Hustai National Park, Mongolia (© Ondrej Prosicky/Shutterstock)

Mission church ruins at Quarai, Salinas Pueblo Missions National Monument, New Mexico (© Thomas Roche/Getty Images)

A beer tent at Oktoberfest in Theresienwiese, Munich, Germany (© Peter Kneffel/picture alliance via Getty Images)

Cuban tody, Alejandro de Humboldt National Park, Cuba (© Bruno D'Amicis/Minden Pictures)

Milky Way over Southwest Alentejo and Vicentine Coast Natural Park, Portugal (© Daniel Garrido/Getty Images)

Splügen Pass, Graubünden, Switzerland (© Roberto Moiola/Getty Images)

Roman-inspired aqueduct, Arkadia Park, Poland (© PATSTOCK/Getty Images)

Inside the Nobel Peace Center, Oslo, Norway (© Ilyas Ayub/Alamy)

Southern white rhinoceros males, Shamwari Private Game Reserve, South Africa (© David Silverman/Getty Images)

Cottonwood trees and red sandstone in Coyote Gulch, Glen Canyon National Recreation Area, Utah (© Stephen Matera/Tandem Stills + Motion)

The Fraser River near Mount Robson, British Columbia, Canada (© phototropic/Getty Images)

Sea otter in Bartlett Cove, Glacier Bay National Park and Preserve, Alaska (© Andrew Peacock/Tandem Stills + Motion)

Venice Skatepark at sunset, Los Angeles, California (© EXTREME-PHOTOGRAPHER/Getty Images)

The Via Krupp footpath on Capri island, Italy (© Mikolaj Niemczewski/Shutterstock)

Container ship near a commercial port in Thailand (© Suriyapong Thongsawang/Getty Images)

Jiaxiu Tower under a full moon, Guiyang, Guizhou province, China (© Wang Yukun/Getty Images)

Fall colors in Shenandoah National Park, Virginia (© Michael Ver Sprill/Getty Images)