(New Salem State Park, 64' x 9', 13-65-a) across IL97/123 in New Salem State Park S. of Petersburg, Petersburg East No. 13 Township, Menard County, IL. IL97/123 S. 2.5 miles from jct with IL123 (Sangamon Av.) in Petersburg to the bridge overhead. (N39° 58.81', W89° 50.33')