The
numbered roads in the Regional Municipality of Durham account for about of the
county road system in the
Canadian province of
Ontario. The
Durham Region Works Department owns and maintains the regional roads and regional highways, while the
Ministry of Transportation of Ontario (MTO) owns and maintains the
King's Highways in the region. The 67 (7 King's Highways, 4 Regional Highways, and 56 Regional Roads) numbered roads provide access to the entirety of the region.
Highway 401 forms the backbone of the region, traveling from the western boundary of the region to the eastern boundary alongside
Lake Ontario, and serving over 200,000 vehicles per day. Several
provincially maintained highways existed in the region prior to 1998, when they were transferred to the Regional Municipality of Durham as part of a province-wide downloading of highways. These routes are now designated as
Durham Regional Highways.