After a request by Nevada County in 1988, the state legislature designated the part of SR 174 in unincorporated Nevada County (between the county line and the Grass Valley city limits) as eligible for the State Scenic Highway System in 1991.
In 1988, Nevada County requested that the state legislature designate a portion of SR 174 in unincorporated Nevada County (between the county line and Grass Valley city limits) as eligible for the State Scenic Highway System. In 1991, the state legislature designated this section of SR 174 as part of the State Scenic Highway System.