Winnemucca Lake is a dry lake bed in northwest Nevada that features the oldest known petroglyphs in North America. Located astride the border between Washoe and Pershing counties, it was a shallow lake until the 1930s, but was dried when a dam and a road were built that combined to restrict and block water flow. It was formerly designated as a Nationa…Winnemucca Lake is a dry lake bed in northwest Nevada that features the oldest known petroglyphs in North America. Located astride the border between Washoe and Pershing counties, it was a shallow lake until the 1930s, but was dried when a dam and a road were built that combined to restrict and block water flow. It was formerly designated as a National Wildlife Refuge, but its status as a refuge was removed due to the lack of water.