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 2 and SH-10 in Welch, Oklahoma. All signage for SH-2 ends at US-59/SH-10 in Welch. However, the official definition of the highway contains an unsigned concurrency with US-59 to the point where it crosses the state line into Kansas. The northern SH-2, between Vinita and the Kansas state line, was once part of US-73. Until the early 1980s a portion of SH-2 was one of the last unpaved state highways in the Oklahoma road network. The section between the communities of Kosoma, Oklahoma and Stanley, Oklahoma in the Kiamichi River Valley, remained gravel. Its builders during the 1930s and 1940s, in