>Tribal elders call the mountain "The place where shamans dream." The tribes consider it a place where ancient ancestors emerged into this world.

>The mountain has been so significant to Indian spiritual leaders for thousands of years that they were reluctant to allow federal archaeologists Stanton Rolf and Cynthia Pinto of the Bureau of Land Management to put its secrets on paper.

https://m.lasvegassun.com/news/1999/oct/05/sacred-spirit-mountain-listed-among-historic-place/

The [Grapevine Valley Petroglyphs] were created between 1100 and 1900 AD. https://en.wikipedia.org/wiki/Grapevine_Canyon_Petroglyphs?wprov=sfla1

Around 10,000 years ago, as the last ice age melted away, the area that is today known as the Mojave Desert was a much wetter place. It was marked by lakes and streams fed by retreating glaciers and sustained by wetter weather patterns. https://www.treehugger.com/deserts-that-used-to-be-verdant-fields-and-forests-4868543#

So somewhere between 10,000 and 1000 years.