S.D. Codified Laws § 31-29-59
In order to provide information to the traveling public, the Department of Tourism may maintain maps and permit informational directories and advertising pamphlets to be made available at safety rest areas, and may establish information centers at safety rest areas for the purpose of informing the public of places of interest within the state and providing other information as may be considered desirable. The department may contract to offer information through advertising or a media display, other than an informational directory or advertising pamphlet. The advertising or media display may be at an information center if the advertising or media display is exhibited solely within the information center and the advertising or media display is not legible from the main traveled way. The proceeds from any advertising or media display shall be deposited into the tourism promotion fund for the operation, maintenance, and expansion of information center exhibits.
SDCL 31-29-59