Photo of the Day

Interior view of a cave
September 8, 2009

Iron Hoop Cave, Alabama

This Month in Photo of the Day: National Geographic Magazine

Millennia in the making, fantastical chambers like this are decorated by the infinitely slow accumulation of minerals (chiefly calcite) deposited by water dripping through rock. Encounters with such rare and fragile beauty are highly prized.

See more photographs from the June 2009 feature story "Deep South."

Photograph by Stephen Alvarez
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