Oklahoma County, Oklahoma Oklahoma County, Oklahoma Oklahoma County is a county located in the central part of the U.S. state of Oklahoma. As of the 2010 census, the population was 718,633, making it the most populous county in Oklahoma. The county seat is Oklahoma City, the state capital. Oklahoma County is at the heart of the Oklahoma City Metropolitan Statistical Area. Oklahoma County is one of seven counties in the United States to share the same name as the state it is located in (the other six counties are Arkansas County, Hawaii County, Idaho County, Iowa County, New York County (known commonly as
Oklahoma State Highway 123 until it changes course and runs due east to Dewey, where it terminates at US-75. Oklahoma State Highway 123 State Highway 123 (abbreviated SH-123) is a state highway in the U.S. state of Oklahoma. It runs a general southwest–northeast course for in northern Oklahoma. SH-123 has no lettered spur routes. SH-123 begins east of Barnsdall, Oklahoma, in Osage County at State Highway 11. It heads north to the Woolaroc Museum before turning northeast. As it approaches the Washington County line, it turns northward to parallel it. SH-123 then enters western Bartlesville, overlapping US-60 for one-fifth of a mile (0.3 km).