The map below is a representation of topography throughout Stearns County. Topography is determined in large part by underlying geology and refined by glaciation and stream erosion. Three major landforms in the County are: hilly lake regions or morainic hills; rolling till plains; and relatively flat outwash plains to the west. Lowest elevation areas tend to follow streams and lake complexes while highest elevation flat areas support agriculture. The prominent hills in the northern and eastern part of the County, created by glacial moraines, provide desirable amenities for developing areas. Development in these hills presents water quality challenges such as protecting soils from erosion (see sidebar) and keeping wooded areas intact.