The mainline route continues east from Sudbury for to North Bay. The northern route rejoins the mainline here, which continues to Arnprior where is upgrades to a freeway numbered 417 as one of Ontario's 400-series provincial controlled-access highways. The freeway continues to Ottawa where the main and southern branches reconverge east of Peterborough. In Southern Ontario, the speed limit is generally on the Trans-Canada, while in Northern Ontario it is . Sections routed along highway 417 feature a higher limit of .