A set of petroglyphs in western Nevada dated in August 2013 to between 10,500 and 14,800 years old, are the oldest rock art ever found in North America. The previous oldest rock art in North America was dated at 6,700 years old and can be found at Long Lake in Oregon.The ancient petroglyphs in Nevada are carved into limestone boulders located on the west side of the now dried-up Winnemucca Lake. The rock art includes both simple petroglyphs such as straight lines and swirls and more complex petroglyphs that resemble trees, flowers, or the veins of a leaf.
There is also a series of abstract designs that look like ovals or diamonds in a chain. The deeply carved lines and grooves in geometric motifs share similarities with the petroglyphs found in Oregon. However, the meaning and symbolism has not yet been deciphered.