Every 100 feet of Iowa's elevation represented by a layer of painted 1/8 inch baltic birch. 12 layers total show the depth carved by glaciers and errosion. Large size measures roughly 22 x 15 inches, small 12 x 8. Both are 1.5 inches at the thickest point and have sawtooth hangers incorporated into the design. They also hang well with adhesive strips!
Iowa Topographic relief