The state trunk highway system includes the following in Custer and Pennington counties:

From a point on U.S. Highway 16 in Custer near the northeast corner of section twentysix, township three south, range four east, thence easterly and northerly via Custer and Keystone to U.S. Highway 16 north of Keystone on the north line of section thirtyone, township one south, range six east.

Source: SL 1984, ch 209, § 12.