(16 sides, donut, IL-16-11) in Tinley Park, Cook County, IL. IL43 (Harlem Av.) N. 0.5 miles from jct with I80 exit 148 on the S. side of Tinley Park, W. on 183rd St. 0.3 miles, N. & immediate E. into the Tinley Park Mental Health Center at 7400 W 183rd St. MUST get permission at the office. (3-15-04, N41° 33.730', W87° 47.670')