Photo of the Day

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January 29, 2009

Pool in Marble Canyon, Arizona

Beyond the roar of the Colorado River, a pool of silence. Discovering this hushed limestone sanctuary at Shinumo Wash in Arizona's Marble Canyon, members of a National Geographic expedition christened it Silver Grotto.

(Photo shot on assignment for "Retracing John Wesley Powell's Historic Voyage Down the Grand Canyon," May 1969, National Geographic magazine)

Photograph by Walter Meayers Edwards

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