Between 1925 and 1930 the then-Main Roads Board reconstructed a route between Hornsby and Calga that had been abandoned some forty years earlier, in order to provide a direct road link between Sydney and Newcastle. In addition a replacement route, from Calga into the gorge of Mooney Mooney Creek and up to the ridge at Kariong above Gosford, was also required. This new Sydney–Newcastle route via Calga and Gosford was some shorter than the previous route via Parramatta, McGraths Hill, Maroota, Wisemans Ferry, Wollombi and Cessnock. At first Peats Ferry was reinstituted to cross the Hawkesbury River, with construction of the bridge not beginning until 1938, due to the Great Depression. Due to the onset of World War II, the Peats Ferry Bridge was not completed until May 1945.