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 3 ran through the area. The combined effect of US-66 being decommissioned and "3A" being a more logical name for an extension of Highway 3 led to the name change. State Highway 3A was decommissioned in 2009. Oklahoma State Highway 3 State Highway 3, also abbreviated as SH-3 or OK-3, is a highway maintained by the U.S. state of Oklahoma. Traveling diagonally through Oklahoma, from the Panhandle to the far southeastern corner of the state, SH-3 is the longest state highway in the Oklahoma road system, at a total length of via SH-3E (see below). Highway 3 begins at the Colorado