Aerial image of the Great Barrier Reef, Australia (© AirPano LLC/Amazing Aerial Agency)

Gemsbok (Oryx gazella) in sand dunes, Namibia (© Sergey Gorshkov/Minden)

South Kaibab Trail in Grand Canyon National Park, Arizona, USA (© Roman Khomlyak/Getty Images)

Wai'anapanapa State Park black sand beach, Maui, Hawaii, USA (© Matt Anderson Photography/Getty Images)

Waterfalls in Sunwapta Valley, Jasper National Park, Canada (© Delpixart/Getty Images)

The chalk cliffs of Étretat, Normandy, France (© MarcelloLand/Getty Images)

Pueblo Bonito, Chaco Culture National Historical Park, New Mexico, USA (© Ian Shive/Tandem Stills + Motion)

Humpback whale (© Philip Thurston/Getty Images)

Porto Cathedral, Portugal (© Reinhard Schmid/Huber/eStock Photo)

Goliath heron, Kruger National Park, South Africa (© Johan Swanepoel/Alamy)

Prickly pear plant, Big Bend National Park, Texas, USA (© Tim Fitzharris/Minden Pictures)

Spanish moss trees over boardwalk in Okefenokee Swamp, Georgia, USA (© Emmer Photo/Alamy)

The city of Passau reflecting in the Danube River, Bavaria, Germany (© Scott Wilson/Alamy)

Synchronous fireflies, Great Smoky Mountains National Park, Tennessee, USA (© Floris Van Bruegel/Minden Pictures)

Hawksbill sea turtle swims near Akajima, Okinawa, Japan (© Robert Mallon/Getty Images)

Castelluccio, Umbria, Italy (© Stefano Termanini/Getty Images)

Common tern father with chick, Nickerson Beach, Long Island, New York, USA (© Vicki Jauron, Babylon and Beyond Photography/Getty Images)

Roe deer fawn running on grass in Normandy, France (© Gerard Lacz/Minden)

Bald eagle, Tongass National Forest, Alaska, USA (© Jaynes Gallery/Shutterstock)

Stonehenge, Salisbury Plain, Wiltshire, England (© Captain Skyhigh/Getty Images)

Amazon rainforest, Peru (© Rhett Ayers Butler/Getty Images)

Monarch butterflies feeding from blazing star wildflowers (© bookguy/Getty Images)

Nha Phu Bay, Nha Trang, Vietnam (© Thang Tat Nguyen/Getty Images)

The Treasury of Petra, Jordan (© WitthayaP/Shutterstock)

Château de Villandry and its garden, Loire Valley, France (© VLADJ55/Shutterstock)

Sedona, Arizona, USA (© Jonathan Ross/Getty Images)

Vernazza in the Cinque Terre region of Italy (© Rubin Versigny/Getty Images)

Banyak Islands, Sumatra, Indonesia (© fbxx/Getty Imagesz)

Brown bear mother and cub, Lake Clark National Park and Preserve, Alaska, USA (© Carlos Carreno/Getty Images)