 After providing access to Tonkawa and Blackwell in Kay County, it crosses into Kansas, becoming the Kansas Turnpike.Some sections of I-35 in Oklahoma City were already built in 1953, before the Interstate system was created.Following the passage of the Federal Highway Act of 1956 that created the Interstate Highway System, the Oklahoma Department of Transportation approved the location of the future interstate north of Oklahoma City to the Kansas state line on a route previously surveyed by the Oklahoma Turnpike Authority for a proposed toll road.