There are many factors that could have made the grand canyon, but noone knows exactly how it was acctualy made.
Water is one of the factors is water, the water would erode the rock over the millions of years it took to form the grand canyon. Ice could also be a factor. Watert would get into the little cracks of the rock, and then it would form into ice, which would make it expand. When the ice would melt, more water would be able to go into the cracks, for years and years. The grand canyon also experienced volcanos and earthquacks, which would break down the rocks and be able to be washed away. With all these factors, we can have a good idea of what made the canyon.
Evans.Laura.How was the grand canyon formed.Web.