The weather has been nice out here in Las Vegas, so I thought I would do a day trip to the Valley of Fire to check out the scenery and spring flowers. The Valley of Fire derives its name from red sandstone formations, formed from great shifting sand dunes during the age of dinosaurs, 150 million years ago. Complex uplifting and faulting of the region, followed by extensive erosion, have created the present landscape. Other important rock formations include limestones, shales, and conglomerates. Prehistoric users of the Valley of Fire included the Basket Maker people and later the Anasazi Pueblo farmers from the nearby fertile Moapa Valley. The span of approximate occupation has been dated from 300 BCE to 1150 CE. Their visits probably involved hunting, food gathering, and religious ceremonies, although scarcity of water would have limited the length of their stay. Fine examples of rock art left by these ancient peoples can be found at several sites within the park.