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 325 to persist on the state highway map, with the legend "(not on highway system)" and no shields. The old US-64 route to Kenton finally received its present-day designation in 1973, when it was numbered after the already-existing NM 325, which once extended to the Oklahoma state line. Oklahoma State Highway 325 State Highway 325, officially, SH-325, is a state highway in the U.S. state of Oklahoma. SH-325 runs for through Cimarron County, Oklahoma, from the New Mexico border west of Kenton to the traffic circle in Boise City. Along the way it provides access to Black Mesa State Park, near