GO Transit bus services are provided throughout the Greater Toronto and Hamilton Area (GTHA) and the Greater Golden Horseshoe. In 2021, the system had a ridership of 4,600,100. While GO Transit started as a single train line in 1967, 15 buses were introduced on September 8, 1970, extending service beyond the original Lakeshore line to Hamilton and Oshawa, as well as providing service north to Newmarket and Barrie. In 1989, GO started running buses between outer train stations and Union at off-peak times when trains were not scheduled. The bus network started expanding beyond train lines, feeding rail service and serving communities beyond the reach of existing trains. In 2000, GO Transit went beyond its existing train corridors and began service along Highway 407, linking York University t