more than from downtown Toronto. Present extrema are Brantford and Kitchener to the west; Orangeville, Barrie and Beaverton to the north; Peterborough and Newcastle to the east; and Niagara Falls to the south. The GO system map shows seven train lines (or corridors), all departing from Toronto's Union Station and mostly named respectively after the outer terminus of train service: Lakeshore West (to Hamilton and Niagara Falls, with buses to Brantford) Lakeshore East (to Oshawa, with buses to Newcastle and Peterborough) Milton Kitchener Barrie Richmond Hill (to Oak Ridges) Stouffville (to Lincolnville, with buses to Uxbridge) Although colours are assigned in a consistent fashion to each line in all official media, in colloquial parlance lines are only ever referred to by their names. Buses are numbered in blocks of 10, corresponding to the nearest train line, with the 40s and 50s reserved for express services along the 407 ETR corridor which does not have a corresponding train line. Operations Rail GO Transit's commuter rail services carry the large majority of its overall ridership. Until 2012, five GO Train lines operated only during weekday rush hour periods in the peak direction (inbound towards Union Station in the morning and outbound in the afternoons and early evenings), with off-peak service on these routes being provided solely by buses. Since then, hourly off-peak train service or better has been added to 5 of these lines. The present off-peak service is as follows: the Lakeshore West and Lakeshore East lines operate half-hourly trains on weekdays off-peak hours and weekends, with weekend service on Lakeshore West extending as far as Niagara Falls. Nearly all trains on the two lines are through-routed, making it possible to travel between Aldershot (or Niagara Falls) and Oshawa without having to change trains at Union Station. They are to date the only lines with all-day train service 7 days a week. the Kitchener line provides hourly, two-way midday and late evening service as far as Mount Pleasant station in Brampton on weekdays only, with two off-peak weekday trains going all the way to Kitchener. There is also one daily round trip to London, Ontario. There is no weekend service. the Barrie line has all-day weekday and weekend train services along the entire line, although most of them only go as far as Aurora the Stouffville has hourly midday and late evening service as far as Mount Joy on weekdays only