SDCL § 31-4-204: State Highway 203 from State Highway 258 to State Training School.

The state trunk highway system includes the following in Aurora County:

From a point on State Highway 258 east of Plankinton near the west line of section twenty-four, township one hundred three north, range sixty-four west, thence north to the entrance of the state training school near the northeast corner of section fourteen, township one hundred three north, range sixty-four west.