The state trunk highway system includes the following in Fall River, Custer, Pennington, Meade, Butte, and Harding counties:

1. (1) From a point on U.S. Highway 18 southeast of Hot Springs northerly via Rapid City to the intersection of U.S. Highway 16B;
2. (2) From a point on State Highway 34 east of Sturgis north to U.S. Highway 212 south of Newell;
3. (3) From a point on U.S. Highway 212 in Newell northerly to State Highway 20;
4. (4) From a point on State Highway 20 east of Buffalo north to the North Dakota state line.

Source: SL 1984, ch 209 , § 51; SL 1986, ch 27 , § 9; SL 1990, ch 225 , § 1; SL 1994, ch 237 , § 2; SL 2001, ch 157 , § 2; SL 2005, ch 150 , § 3.