When the Department of Engineering laid out the initial state highway system after the state's voters approved a bond issue to pay for it in 1910, they included Route 5, connecting Santa Cruz and Oakland with Stockton via Altamont Pass. San Joaquin County paved the portion near Tracy with asphalt with their own bond issue, passed in 1909, and the state later resurfaced it with concrete. In addition, the new concrete road bypassed Banta, which the old county road had passed through via Banta Road, F Street, and Grant Line Road. Otherwise, the road was relatively direct, coming down from Altamont Pass onto Grant Line Road, following Byron Highway into Tracy, and leaving east and northeasterly on 11th Street to the San Joaquin River at the Mossdale Crossing. The Lincoln Highway Association chose this route in 1913 for their transcontinental highway, where it remained until the Carquinez Bridge opened in 1927, creating a shorter route via Vallejo. In 1926, the American Association of State Highway Officials designated the Stockton-Bay Area route as US 48, which was absorbed by an extension of US 50 by the early 1930s.