Feathered fathers
King penguin father checking egg (© McDonald Wildlife Photography Inc./Getty Images)

Feathered fathers
King penguin father checking egg (© McDonald Wildlife Photography Inc./Getty Images)

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3.5 MB

An ocean's frozen cathedral
Arched iceberg floating off the western Antarctic Peninsula, Southern Ocean (© Steven Kazlowski/Nature Picture Library)

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3.6 MB

An ocean's frozen cathedral
Arched iceberg floating off the western Antarctic Peninsula, Southern Ocean (© Steven Kazlowski/Nature Picture Library)

A story rising in bronze
National Museum of African American History and Culture, Washington, DC (© Walter Bibikow/Alamy)

A story rising in bronze
National Museum of African American History and Culture, Washington, DC (© Walter Bibikow/Alamy)

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3.5 MB

A rock-solid marvel
Aerial view of the ruins of Sacsayhuamán, Cusco, Peru (© Creative-Family/Getty Images Plus)

A rock-solid marvel
Aerial view of the ruins of Sacsayhuamán, Cusco, Peru (© Creative-Family/Getty Images Plus)

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3.6 MB

Twist your way up
Tremola Road on the Saint Gotthard Pass in Airolo, Switzerland (© Sandro Bisaro/Getty Images)

Twist your way up
Tremola Road on the Saint Gotthard Pass in Airolo, Switzerland (© Sandro Bisaro/Getty Images)

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3.6 MB

Nature's reef keepers
Hawksbill sea turtle pair near Seven Mile Beach, Grand Cayman, Cayman Islands (© Alex Mustard/Nature Picture Library)

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3.5 MB

Nature's reef keepers
Hawksbill sea turtle pair near Seven Mile Beach, Grand Cayman, Cayman Islands (© Alex Mustard/Nature Picture Library)

Aged to scenic perfection
Great Smoky Mountains National Park, Tennessee (© Mint Images/Getty Images)

Aged to scenic perfection
Great Smoky Mountains National Park, Tennessee (© Mint Images/Getty Images)

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3.6 MB

History flies high
US flags surrounding the Washington Monument, Washington, DC (© Orhan Cam/Shutterstock)

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3.6 MB

History flies high
US flags surrounding the Washington Monument, Washington, DC (© Orhan Cam/Shutterstock)

Layers of change
Sunset in Badlands National Park, South Dakota, USA (© Troy Harrison/Getty Images)

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3.6 MB

Layers of change
Sunset in Badlands National Park, South Dakota, USA (© Troy Harrison/Getty Images)

A flash in flight
European bee-eater, Sierra de Grazalema Natural Park, Cádiz, Spain (© Andres M. Dominguez/Nature Picture Library)

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3.5 MB

A flash in flight
European bee-eater, Sierra de Grazalema Natural Park, Cádiz, Spain (© Andres M. Dominguez/Nature Picture Library)