The following are the maximum speeds on certain highways in Custer County:

1. (1) State Trunk Highway 36 beginning at the junction of U.S. Highway 16A near the east gate of Custer State Park, then northeasterly for 0.7 mile, thirty-five miles per hour; then northeasterly for 8.51 miles to the State Trunk Highway 79 junction, fifty miles per hour;
2. (2) U.S. Highway 16 beginning 1.08 miles west of the junction with U.S. Highway 385 in the city of Custer, then east for 0.3 mile, forty-five miles per hour; then east for 0.78 mile to the junction with U.S. Highway 385, thirty-five miles per hour;
3. (3) U.S. Highway 16A beginning at the junction with U.S. Highway 16 in Custer, then easterly for 0.37 mile, twenty-five miles per hour; then easterly for 0.25 mile, thirty-five miles per hour; then easterly for 1.03 miles, forty-five miles per hour; then easterly to the west border of Custer State Park, fifty-five miles per hour;
4. (4) U.S. Highway 16A commencing at the Pennington-Custer county line, then southeasterly along a circuitous route in Custer County to a point 2.9 miles northwest of the north boundary of Custer State Park, twenty-five miles per hour; then southeasterly for 2.9 miles to the north boundary of Custer State Park, thirty-five miles per hour;
5. (5) U.S. Highway 16A within the boundary of Custer State Park, thirty-five miles per hour;
6. (6) State Trunk Highway 89 beginning at the junction with State Highway 87 near Sylvan Lake, then south 3.8 miles, thirty-five miles per hour, then south to the junction with U.S. Highway 16A near Custer, forty-five miles per hour;
7. (7) U.S. Highway 385 within the boundaries of Wind Cave National Park, forty-five miles per hour;
8. (8) State Trunk Highway 40 beginning at the north junction of State Trunk Highway 79 at the west edge of Hermosa, then east for 0.7 mile, thirty-five miles per hour; then east for 0.2 mile, fifty miles per hour;
9. (9) State Trunk Highway 87 beginning at the north boundary line of Custer County, then south for 13.9 miles, twenty-five miles per hour; then south for 2.3 miles to the east junction with U.S. Highway 16A, thirty-five miles per hour; then from the west junction with U.S. Highway 16A south to the boundary of Custer State Park, thirty-five milers per hour;
10. (10) U.S. Highway 385 beginning at the junction with U.S. Highway 16 in Custer, then south for 0.2 mile, thirty-five miles per hour, then south for 0.23 mile, forty-five miles per hour;
11. (11) U.S. Highway 385 beginning 0.3 mile north of the junction with State Trunk Highway 89 by Pringle, then south and east 6.37 miles, forty-five miles per hour;
12. (12) U.S. Highway 16 beginning at the junction with U.S. Highway 385 in the city of Custer, then easterly to the intersection of Fifth Street, twenty-five miles per hour; then northerly for 0.5 mile, twenty-five miles per hour; then northerly for 0.5 mile, thirty-five miles per hour; then north for 0.2 mile, forty-five miles per hour; then northerly for 5.91 miles to the Pennington County line, sixty miles per hour;
13. (13) State Trunk Highway 40 beginning at the Pennington-Custer county line, then southeast for 6.48 miles, fifty-five miles per hour;
14. (14) U.S. Highway 16 beginning eleven miles east of the South Dakota-Wyoming border, then easterly for 0.5 mile, fort-five miles per hour, then easterly for 1.5 miles, thirty-five miles per hour, then easterly for 2.1 miles, forty-five miles per hour;
15. (15) State Trunk Highway 79 beginning at the Fall River County line, then north to a point 0.50 mile south of the junction with State Trunk Highway 36, seventy miles per hour for the segments of highway that are four-lane divided sections; then north for 1.25 miles, sixty-five miles per hour; then north for 0.90 mile through Hermosa, fifty-five miles per hour; then north to the Pennington County line, seventy miles per hour; and
16. (16) State Trunk Highway 87 within the boundaries of the Wind Cave National Park, thirty-five miles per hour.

Source: SL 1975, ch 16, § 1; 7 SDR 100, effective April 27, 1981; 11 SDR 22, effective August 12, 1984; 13 SDR 52, effective November 6, 1986; 13 SDR 129, 13 SDR 134, effective July 1, 1987; 16 SDR 152, effective March 28, 1990; 21 SDR 171, effective April 2, 1995; 22 SDR 165, effective June 2, 1996; 23 SDR 132, effective February 27, 1997; 27 SDR 15, effective August 30, 2000; 32 SDR 109, effective December 26, 2005; 36 SDR 163, effective May 3, 2010; 40 SDR 58, effective October 9, 2013; 43 SDR 8 7 , effective December 1 3 , 2016 ; 44 SDR 17, effective August 8, 2017 ; 46 SDR 26, effective September 2, 2019; 47 SDR 27, effective September 14, 2020 ; 51 SDR 12, effective August 12, 2024 .

General Authority: SDCL 32-25-7 , 32-25-7.1 .

Law Implemented: SDCL 32-25-7 , 32-25-7.1 .

Prior versions effective: 2020-09-14, 2019-09-02, 2017-08-08, 2016-12-13, 2013-10-09.