Oklahoma State Highway 270 1979, US-270 ran through Oklahoma City on surface streets. It left the city and ran through Choctaw concurrent with US-62. US-270 split away from US-62 in Harrah, and continued on to Shawnee on what is now SH-270. On March 5, 1979, US-270 was rerouted to run concurrent with Interstate 40 from south of Calumet in Canadian County through the Oklahoma City metro, exiting the Interstate onto a surface alignment in Shawnee. Presumably, SH-270 was commissioned the same date. The realignment of US-270, with SH-270 on the old alignment between Harrah and Shawnee, appears on the 1979 state map. SH-270 followed
Oklahoma State Highway 171 comes to an end at US-56. The route of the present-day SH-171 was first shown as a state highway on the 1975 official state map, implying its creation in 1974. On this edition of the map only, it is shown as State Highway 170. By 1976, it was shown as SH-171. The route has always been paved, and follows the same routing that it did in 1974. Oklahoma State Highway 171 State Highway 171, abbreviated as SH-171, is a state highway in Cimarron County, Oklahoma, in the Oklahoma Panhandle. It runs for north and south through the eastern part of