What era did the Grand Canyon form in?

The Grand Canyon primarily formed during the late Cenozoic Era, specifically through processes that began around 5 to 6 million years ago. However, the rock layers exposed in the canyon date back much further, with some formations dating to the Precambrian era, around 1.8 billion years ago. The canyon's current shape and depth resulted from erosion by the Colorado River, along with geological uplift and other erosional processes over millions of years.