Millennium Bridge with St. Paul's Cathedral in the background, London, England (© Scott Baldock/Getty Images)

Great Barrier Reef, Queensland, Australia (© AWL Images/Danita Delimont)

Sunwapta Falls in Jasper National Park, Canada (© Schroptschop/Getty Images)

Mountain bikers on White Rim Road in Canyonlands National Park, Utah (© Grant Ordelheide/Tandem Stills + Motion)

Pont Fawr, a stone arch bridge in Llanrwst, Wales, UK (© Pajor Pawel/Shutterstock)

Synchronous fireflies illuminate the forests of Great Smoky Mountains National Park, Tennessee (© Floris van Breugel/Minden Pictures)

Walter's Wiggles on the Angels Landing Trail in Zion National Park, Utah (© Dennis Frates/Alamy)

Hermitage of La Pertusa, Lleida province, Spain (© bbsferrari/Getty Images)

Galápagos sea lion off the shore of Fernandina Island, Galápagos Islands, Ecuador (© Tui De Roy/Minden Pictures)

Baron Lake and Upper Baron Lake in the Sawtooth Wilderness in Idaho (© Patrick Brandenburg/Tandem Stills + Motion)

Griboyedov Canal and the Church of the Savior on Spilled Blood in Saint Petersburg, Russia (© Tomas Sereda/Getty Images)

Santa Elena Canyon under the Milky Way in Big Bend National Park, Texas (© Stanley Ford/Shutterstock)

The Dourbie Gorge Corps Mill and adjoining bridge in Grands Causses Regional Nature Park, France (© Hemis/Alamy)

US Flag Plaza at Liberty State Park in Jersey City, New Jersey (© Antonino Bartuccio/eStock Photo)

Surfer on the beach in Medewi, Bali, Indonesia (© helivideo/Getty Images)

St. Stephen's Green in Dublin, Ireland (© L_E/Shutterstock)

Beaver Falls on Havasu Creek in the Grand Canyon, Arizona (© Edwin Verin/Alamy)

The Bojo River in Cebu, Philippines (© Amazing Aerial Agency/Offset by Shutterstock)

The Texas African American History Memorial on the State Capitol grounds in Austin, Texas (© Moab Republic/Shutterstock)

Artist Saype's 'Beyond Walls' installation in the Parc de la Grange, Geneva, Switzerland (© Valentin Flauraud/Shutterstock)

A bearded emperor tamarin monkey carrying a baby (© Chris White/iStock/Getty Images Plus)

Male southern double-collared sunbird on a rocket pincushion flower, Cape Town, South Africa (© Martin Willis/Minden Pictures)

Bull Point in Devon, England (© Robert Harding World Imagery/Offset by Shutterstock)

Midsummer light captured at a lake near the city of Örebro, Sweden (© Anders Jorulf/Getty Images)

German navy tall ship Gorch Fock in waters off Reykjavík, Iceland (© DEEPOL by plainpicture/Henn Photography)

Grandidier's baobab forest near Morondava, Madagascar (© Thomas Marent/Minden Pictures)

The Sanctuary of Madonna della Corona in Italy (© Volodymyr Kalyniuk/Alamy)

The Empire State Building lit up in honor of Pride Week in 2014, New York City (© C. Taylor Crothers/Offset by Shutterstock)

Goats in an argan tree near Essaouira, Morocco (© Nizz/Shutterstock)

Jabiru storks in the Pantanal of Brazil (© Juan-Carlos Munoz/Minden Pictures)