Outwash plains are flat areas formed by the deposition of sediments from melting glaciers. As glaciers retreat, they release meltwater that carries sand, gravel, and silt away from the ice. This material is then deposited in broad, gently sloping areas, creating a landscape that is often characterized by a mix of sediment types. These plains are typically found in regions that were once covered by ice sheets, such as parts of North America and Europe. They play an important role in the ecosystem, providing fertile soil for agriculture and serving as habitats for various plants and animals.