North America's Oldest Petroglyphs Discovered...
The rock carvings on the Pyramid Lake Indian Reservation in Nevada are fairly well known, but no one knew just how old they were before paleoclimatologist Larry Benson dated them using the history of the area's climate."...
https://www.neatorama.com/2013/08/17/North-Americas-Oldest-Petroglyphs-Discovered/
