Find a Freight Forwarder in South Dakota with our Comprehensive listing. South Dakota is a state in the Midwest where the Missouri River, one of the largest tributaries to the mighty Mississippi River, divides the state in two. This large river makes an excellent shipping waterway that has been utilized for nearly 200 years. Major highways such as I-90 and I-29 criss-cross the state as part of the excellent interstate system that makes trucking a major industry in South Dakota. Railroads have been essential to South Dakota’s history, beginning during the 19th century boom in railway construction in America. The two largest trucking and rail hubs are located in Sioux Falls and Rapid City, two cities on opposite ends of the state along I-90.