The Tennessee River has historically been a major highway for riverboats through the South, and today they are frequently used along the river. Major ports include Guntersville, Chattanooga, Decatur, Yellow Creek, and Muscle Shoals. This river has contributed greatly to the economic and industrial development of the Tennessee Valley as a whole. The economies of cities such as Decatur and Chattanooga would not be as dynamic as they are today, were it not for the Tennessee River. Many companies still rely on the river as a means of transportation for their materials. In Chattanooga, for example, steel is exported on boats, as it is much more efficient than moving it on land.