(Missionary Ridge, 932', c1950) under Missionary Ridge in Chattanooga, Hamilton County, TN. TN316 (Martin Luther King Dr.) E. 0.2 miles from jct with I124 in Chattanooga, continue E. on US11 3.1 miles to the tunnel. (N35 01.750 W85 15.442) Photo by Jack Schmidt 7-16-08.