Controlled-access highway in Ontario, Canada
King's Highway403 (pronounced "four-oh-three"), or simply Highway403, is a 400-series highway in the Canadian province of Ontario that travels between Woodstock and Mississauga, branching off from and reuniting with Highway 401 at both ends and travelling south of it through Hamilton (where it is also known as the Chedoke Expressway) and Mississauga. It is concurrent with the Queen Elizabeth Way (QEW) for from Burlington to Oakville. The Highway403 designation was first applied in 1963 to a short stub of freeway branching off the QEW at Burlington, and the entire route was completed on August15, 1997, when the section from Brantford to the then-still independent Town of Ancaster was opened to traffic. The section of Highway403 between Woodstock and Burlington was formally dedicated as the Alexander Graham Bell Parkway on April27, 2016, in honour of Alexander Graham Bell.
The majority of Highway403 is surrounded by suburban land use, except west of Hamilton, where it passes through agricultural land; Brantford is the only urban area through this section. In Hamilton, Highway403 descends the Niagara Escarpment, then wraps around the northern side of Hamilton Harbour to encounter the QEW. From there, co-signed with the QEW, it travels straight through Burlington and Oakville, departing from the QEW to the north at the Mississauga–Oakville boundary. The freeway then crosses through the centre of Mississauga in an east–west direction, serving its city centre. Turning north, Highway403 splits up into a collector-express system, with the express lanes defaulting to Highway401 east of that interchange, while the collector lanes thereafter continues north as Highway 410 to Brampton.
Route description.
Woodstock to Burlington.
Highway403 begins at a junction with Highway401 on the outskirts of Woodstock. The eastbound lanes split from eastbound Highway401, whereas the westbound lanes merge into westbound Highway401.
It travels along the back lot lines of the second concession south of former Highway2.
This first section of the highway is also the least travelled portion, with approximately 20,900vehicles using it on an average day in 2016.
The highway passes beneath Oxford County Road 55 (formerly Highway53) and curves southeast. After crossing into the third concession, it curves back to the east. The highway travels straight for several kilometres, meeting with the southern leg of Highway 24, which travels south to Simcoe.
The highway crosses the Grand River to the south of Paris, then passes over former Highway2 as it enters Brantford. As it passes through Brantford, the highway angles southeast and passes beneath the northern leg of Highway24 and then the Wayne Gretzky Parkway. The route exits the small city to the east and curves northeast shortly thereafter. It travels between Jerseyville Road and former Highway2 to Ancaster, jogging to avoid cutting through Dunmark Lake. As the freeway enters Ancaster, it once again crosses former Highway2 and dips through the southern side of the town. Since July 12, 2024, the speed limit on the stretch between the west end of the highway and Brantford and the stretch between Brantford and Hamilton is .
East of Ancaster, the freeway passes through a short greenbelt, with Hamilton Golf and Country Club lying to the north. A divided segment of Highway 6 meets the freeway and continues concurrently with it through Hamilton; to the south, Highway6 travels to Hamilton International Airport, Caledonia, and Jarvis at Highway 3. Continuing east, Highway403 and Highway6 curve north into Hamilton and meet the Lincoln M. Alexander Parkway before abruptly turning to the east and descending the Niagara Escarpment. Scenic views of Hamilton, its harbour, port and Lower Princess Falls are along this steep descent. At the bottom of the escarpment the highway travels through a narrow, heavily developed corridor alongside former Highway 8. It passes beneath multiple bridges in a depressed trench, eventually curving north at a sharp corner and passing beneath more bridges. This section features a reduced speed limit of as opposed to . The highway returns to ground level alongside the Chedoke Creek, a now-channelized river from which the freeway may take its name.
As the freeway continues north, it crosses an isthmus between Hamilton Harbour and Cootes Paradise alongside several roads which it has served to replace. It circles around the northern shore of Hamilton Harbour and returns to an eastward orientation. The concurrency with Highway6 ends at an interchange where Highway403 continues east and Highway6 departs north towards Guelph. The freeway continues straight for several kilometres, passing by the Burlington Transmission Station, until it approaches the Freeman Interchange where the opposing carriageways split apart to accommodate the left-hand exit/entry of the flyover ramps marking the western terminus of Highway 407, then it merges with Queen Elizabeth Way.
Burlington to Mississauga.
Highway403 travels concurrently with the QEW for between the Freeman Interchange and Oakville, a straight section surrounded almost entirely by commercial units and warehouses.
At the Ford Assembly Plant near the Halton–Peel regional boundary, Highway403 branches off from the QEW as it crosses Ford Drive (Halton Regional Road 13), with the eastbound lanes diving under the QEW and Upper Middle Road before reuniting with the westbound carriageway. After running north–south for along the western edge of Mississauga, Highway403 meets with Highway 407 again at a combination interchange where the two freeways curve 90 degrees to avoid crossing each other. Approaching this junction Highway403 westbound traffic defaults onto Highway407 so motorists have to continue on Highway403 via a semi-directional flyover that arcs from the west to the south. This north–south segment of Highway403 was originally planned as a temporary routing to be bypassed by a new direct Oakville-Burlington link; but in 1995 this routing became permanently part of Highway403 when the proposed link instead became part of Highway407.
Highway407 continues to the north and west, while Highway403 turns east to follow alongside a hydro corridor through the centre of Mississauga. A portion of the Mississauga Transitway express bus service utilizes the freeway's right shoulders between Erin Mills Parkway and Mavis Road. Between Highway407 and Highway401, high-occupancy vehicle (HOV) lanes are present in the left shoulder lanes for vehicles with at least one passenger.
Sandwiched between residential subdivisions on both sides, the freeway soon thereafter crosses the Credit River. On the other side of the river, between the interchanges with Mavis Road and Hurontario Street (formerly Highway 10), Highway403 skirts to the north of downtown Mississauga, as well as the Square One Shopping Centre.
After a split with Eastgate Parkway where exiting drivers can access Eglinton Avenue or Cawthra Road at a signalized intersection, Highway403 abruptly curves to the north. As the curve straightens and approaches the Parlo interchange with Eglinton Avenue, Cawthra Road's northbound lane converges with the onramps from Eglinton to form the eastbound collector lanes, soon joined by the eastbound express-to-collector transfer that also marks the start of another HOV lane. For the westbound collector-express system of Highway403, after an offramp to Eglinton Avenue there is collector-to-express transfer; thereafter the collector lanes including the onramps from Eglinton split off and continues south as Cawthra Road, with a signalized intersection for Eastgate Parkway or Highway403 westbound. The portion of the highway between Hurontario Street and Eglinton Avenue is the busiest along the route, with approximately 180,000vehicles travelling it on an average day in 2016.
After crossing Matheson Boulevard, the freeway's central HOV lanes terminate and merge with the express lanes. The freeway then approaches a sprawling interchange, with the express lanes curving east and defaulting to Highway401's express lanes east of that junction, while the collector lanes (including its HOV lane) pass under several sets of flyovers and thereafter continues north as Highway 410 to Brampton. The freeway's collector lanes also have connecting ramps to both directions of Highway401's collector lanes.
History.
Though one of the first divided highways conceived for Ontario, Highway403 is one of the most recently completed freeways in the province; the multiple segments of the route did not become continuous until 2002. Planning for the route was underway by 1958, as a portion of QEW was realigned from its original alignment of Middle Road to the "Freeman Diversion" which also included three-legged junction for the future Highway403. Sections of Highway403 through Hamilton opened between December 1963 and September 1969, with that stretch known as the "Chedoke Expressway". An isolated section known as the Brantford Bypass was opened in October 1966, and would remain unconnected to other freeways for over 20years. Plans for a third segment through Mississauga (originally known as the Hamilton Expressway) were contemplated throughout the 1960s, but were not finalized until late 1977, after which construction began. Portions opened at both ends in 1980 and 1981, while the central gap, crossing the Credit River, was completed in December 1982.
Construction to bridge the gaps in Highway403 between Ancaster and Woodstock was carried out over three major phases. The first phase was a short extension of the Brantford Bypass beginning in 1975, however motorists would have to continue on Highway2/53 to reach Highway401. Later, work began to connect that extension with Highway401 near Woodstock, which opened in 1988. An existing portion of Highway2 served as the connector between the Woodstock-Brantford and Ancaster-Hamilton segments, until the last phase between Ancaster and Brantford finally opened in 1997.
The final discontinuity, between Burlington and Oakville, was signed as a concurrency with the QEW in 2002. Originally, Highway403 was to be extended westward from Oakville to connect directly with the Burlington-Brantford segment, bypassing the north–south routing of Highway403 along the Mississauga-Oakville boundary that would then be re-designated as part of the proposed Highway407. Budget shortfalls in 1995 resulted in a change of plans, so Highway403 retained the existing north–south segment in Oakville, while the vacant corridor previously intended for Highway403 from Oakville to Burlington has since been occupied by the westmost extension of Highway407 ETR that opened in 2001. 
The stretch of Highway403 between Woodstock and Burlington, whose separate segments were previously known as the "Brantford Bypass" and "Chedoke Expressway", was formally dedicated as the "Alexander Graham Bell Parkway" on April27, 2016, in honour of Alexander Graham Bell. Some sources like Google Maps have erroneously referred to the entirety of Highway403 as the "Chedoke Expressway". 
Predecessors.
The corridor that connects London and Hamilton has always been considered important to Ontario. In late October 1793, Captain Smith and 100 Queen's Rangers returned from carving The Governor's Road (Dundas Street) through the thick forests between Dundas and the present location of Paris. John Graves Simcoe was tasked with defending Upper Canada from the United States following the American Revolution and with opening the virgin territory to settlement. After establishing a "temporary" capital at York, Simcoe ordered an inland route constructed between Cootes Paradise at the tip of Lake Ontario and his proposed capital of London. By the spring of 1794, the road was extended as far as La Tranche, now the Thames River. Today, most of this route forms part of former Highway 2 and former Highway 5.
The paving of the divided four-lane Middle Road, with gentle curves, a grass median, and grade-separated interchanges, would set the stage for the freeway concept. It was the first intercity freeway in North America when it opened in June 1939.
Thomas McQuesten, the new minister of the Department of Highways and the man most responsible for the Middle Road, decided to apply the concept to sections of Highway2 plagued with congestion. A portion east of Woodstock was rebuilt in this fashion, but World War II would put an end to McQuesten's ambitions, at least temporarily.
Initial construction.
The end of the Korean War in 1953 heralded the resumption of freeway construction in Ontario; the advances in machinery more than made up for lost time.
The construction of Highway401 across the province took first priority. However, the opening of the section of Highway 401 from Highway4 near London to Highway2 east of Woodstock on May31, 1957 would complete part of the route required between London and Hamilton.
By 1958, planning on the "Chedoke Expressway", or Controlled Access Highway403, was well underway,
though plans for a four-lane freeway between Woodstock and Hamilton existed as early as 1954.
The opening of the "Freeman Diversion" alignment of the QEW in August 1958 provided a connection point for the future Chedoke Expressway,
and construction began the same day that the Burlington Bay James N. Allan Skyway opened: October31, 1958.
Highway403 between Longwood Road (Highway2) and the QEW was opened to traffic on December1, 1963 at a length of . Work was already underway on the next section of the route that would extend it to Aberdeen Avenue.
That section opened on July9, 1965, extending the freeway