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 other materials. This sediment is then deposited in layers, creating a broad, flat landscape. These plains are often found in regions that were once covered by ice during the last Ice Age. They can support diverse ecosystems and are important for agriculture due to their fertile soils. Outwash plains are commonly associated with features like kettle lakes and moraine formations, which are remnants of glacial activity.