wall

El Capitan at Sunset in Yosemite.
Taken on September 5, 2011

Photography by Brian Petersen at http://www.brianapetersen.com

A fortified wall in northern China, extending some 2,400 km (1,500 miles) from Kansu province to the Yellow Sea north of Beijing. It was first built c. 210 bc, as a protection against nomad invaders. The present wall dates from the Ming dynasty.

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