Great Lakes wave sizes can be large, but one major difference between freshwater and saltwater is buoyancy. Boards do not float as readily on freshwater because it has a much lower density than saltwater. Lake surfers have to use wider, thicker boards than their ocean-going peers. Traditional "longboards" are a common sight on the lakes. Some surfers who prefer shorter lengths rely on lighter, more buoyant epoxy boards instead of standard fiberglass ones.