Photo of the Day 40

Surf on Beach, Canary Islands, 2006

Photograph by Justin Guariglia

Surf spreads a foamy swath over a black beach in Gomera in Spain's Canary Islands. Gomera's tortuous geography—desert lowlands twist upwards into a soaring cloud forest—initiated the evolution of silbo, an indigenous six-note whistling language that allows the island's residents to efficiently communicate over hill and vale.

(Photo shot on assignment for, but not published in, "The Quietest Place on Earth," September 2006, National Geographic Traveler magazine)