S.D. Codified Laws § 7-1-20
Beginning at a point where the township line between townships one hundred seventeen and one hundred eighteen north intersects the boundary line between the states of South Dakota and Minnesota, thence west and along said township line to the northwest corner of township one hundred seventeen north of range fifty, west of the fifth principal meridian; thence south and along the range line between ranges fifty and fifty-one to the southwest corner of township one hundred thirteen north of range fifty west; thence east and along the township line between townships one hundred twelve and one hundred thirteen north, to the boundary line between the states of South Dakota and Minnesota; thence north and along said line to the place of beginning.
SDCL 7-1-20