Huffington Post - Megan Gannon, 8/14/13
Researchers found that petroglyphs discovered in western Nevada are at least 10,500 years old, making them the oldest rock art ever dated in North America.
On the west side of Nevada's dried-up Winnemucca Lake, there are several limestone boulders with deep, ancient carvings; some resemble trees and leaves, whereas others are more abstract designs that look like ovals or diamonds in a chain.
The true age of this rock art had not been known, but a new analysis suggests these petroglyphs are the oldest North America, dating back to between 10,500 and 14,800 years ago.
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