Golden Gate Bridge and Marin Headlands photographed from Golden Gate Overlook in San Francisco, California

Hanging bridge in the Monteverde Cloud Forest Reserve, Costa Rica

Alhambra in Granada, Andalusia, Spain

Kornati National Park, Croatia

Florida red-bellied turtle in Rainbow Springs, Rainbow Springs State Park, Florida

A Burchell's zebra and a cattle egret at the Rietvlei Nature Reserve in South Africa

Albion Falls, Hamilton, Ontario, Canada

Honey bee flying over crocuses in the Tatra Mountains, Poland

Glass bridge of Zhangjiajie, Hunan, China

Museum at Prairiefire, Overland Park, Kansas

Salt ponds of Maras in Peru's Sacred Valley of the Incas

Burrowing owl chicks gaze out from among flowers near the Pawnee National Grassland in Colorado

Panoramic view of the Bernina Range with blood moon, Eastern Alps, Engadin, Switzerland

Windmills, Kinderdijk, Netherlands

Masai giraffe in Maasai Mara, Kenya

Nurses serving with the American Red Cross in Paris, France, in May 1919

The village of Oia on the island of Santorini, Greece

Panther Creek Falls in spring, Gifford Pinchot National Forest, Washington

View of Göreme from an observation deck, Göreme National Park, Cappadocia, Turkey

Koala mother and 8-month-old joey, Queensland, Australia