Rivers shape the landscape over time through a process called erosion. As rivers flow, they carry sediment and materials like rocks and soil downstream. The force of the water can wear away the land, creating valleys and canyons. Additionally, rivers deposit sediment along their banks and deltas, which can build up over time to form new landforms. This constant movement of sediment and erosion by rivers can change the landscape, creating features such as meanders, floodplains, and river terraces.