What causes canyons to form over time?

Canyons form over time through the process of erosion caused by rivers, wind, and weathering. Flowing water cuts through rock layers, deepening and widening the valley. Sediments carried by the river enhance the erosion process. Weathering from temperature changes and chemical reactions also weakens the rock. Famous examples, like the Grand Canyon, showcase how millions of years of erosion can create dramatic landscapes.