 On September 26, 1939 when the state highway commission approved the General Redesignation of the State Highway System and created the state's Highway Designation Files, SH 118 had been extended north to Kent, replacing SH 233.With this new designation, the route was largely the same as the present with the exception of taking a more westerly path at a point near Adobe Walls Mountain in southern Brewster County in order to terminate at Terlingua rather than Study Butte; although, except for the stretch between Alpine and Fowlkes Ranch, the road was unpaved and even classified as primitive in places.The stretch of the road through Fort Davis to the present intersection with SH 166 at Nunn Hill was concurrent with SH 166.