Retaining walls are structures designed to restrain soil to a steep or vertical slope. There are several types of retaining walls including gravity, cantilevered, sheet piling, bored pile, anchored, soil nailing, soil-strengthened, and mechanical stabilization walls. They are used to create boundaries between different land elevations or to reshape landscapes with undesirable slopes. Common retaining wall types are gravity walls which rely solely on their own weight, cantilever walls made of reinforced concrete with a thin stem and base slab, and counterfort walls which are cantilever walls with buttresses for additional lateral support.