Children climb the steep sides of an ancient handmade brick cistern containing town water. Nyhavn canal A flock of White-faced Whistling

A flock of White-faced Whistling Ducks in flight over a wetland

A small boy and his dog digging in the sand on a tropical island beach at low tide with their feet

The weathered texture of wall timbers outside the hut of Antarctic explorer Ernest Shackleton

A solitary hiker on the frozen and barren wasteland of folded ice on the Greenland Ice Sheet

In late summer dry farmland grasses and crops wither in the heat

Children climb the steep sides of an ancient handmade brick cistern containing town water. Nyhavn canal A flock of White-faced WhistlingChildren climb the steep sides of an ancient handmade brick cistern containing town water. Kashan, Isfahan Province, Islamic Republic of Iran.