Oklahoma State Highway 4 Oklahoma State Highway 4 State Highway 4, abbreviated as SH-4 or OK-4, is a designation for two distinct highways maintained by the U.S. state of Oklahoma. One of them serves as an important route through the suburbs west of Oklahoma City, while the other connects US-259 to the Arkansas state line west of Cove, Arkansas. SH-4 has no lettered spur routes. The two SH-4s were never connected. The Central Oklahoma highway was established in 1941 and gradually extended to its present extent between then and 2003. The Eastern Oklahoma highway was originally numbered SH-21, and was renumbered to SH-4 in
Oklahoma State Highway 8 Oklahoma Transportation Commission applied the national highways to Oklahoma's state highway system on 1926-11-26. Three U.S. highways were assigned to portions of what was then SH-8: U.S. Highway 64 was added to a segment of highway south of Cherokee, U.S. Highway 66 was added between Bridgeport and Geary, and U.S. Highway 70 was added from the Texas state line to Randlett. US-66 and 64 merely ran concurrently with SH-8. However, US-70 completely replaced the state highway, which was truncated so that its southern terminus was at US-70 in Randlett. By 1936, several U.S. highways had been added to the system