South Dakota Transportation

Two major interstate highways pass through South Dakota: Interstate 90, which runs east and west; and Interstate 29, running north and south in the eastern portion of the state. The counties and towns along Interstate 29 make up what is locally referred to as "the I-29 corrider". This area features generally higher rates of population and economic growth than areas in eastern South Dakota that are further from the interstate. Interstate 90, being a major route between western national parks and large cities to the east, brings many out-of-state travellers through South Dakota, thus helping to boost the tourism and hospitality industries. Also located in the state are the shorter interstates 190, a spur into central Rapid City, and 229, a loop around eastern and southern Sioux Falls.

Several major U.S. highways pass through the state. U.S. routes 12, 14, 16, 18, and 212 travel east and west, while U.S. routes 81, 83, 85 and 281 run north and south.

South Dakota license plates are numbered by county, with the first digit referring to the county of origin. Such a numbering system allows one to easily determine where the vehicle was registered. Counties 1–9 are ranked by 1950 population [5], and counties 10–64 are numbered alphabetically.

• List of South Dakota railroads
• Category: Transportation in South Dakota

A rest stop "tipi" is a frequent sight on a trip across the state