Ontario Highway 73 History - The King's Highways of Ontario

King's Highway 73 was a short collector highway which linked Port Bruce and Aylmer to Highway 401 near Dorchester. The highway was 39 km in length and it existed up until the late 1990s, when it was downloaded to the Counties of Elgin and Middlesex. The history of Highway 73 dates back to 1937, when the Department of Highways assumed the county road from Port Bruce to Dorchester Road (known as Hamilton Road today) as a new King's Highway. Contrary to popular belief, Highway 73 did not connect directly to Highway 2 during its 61-year history, even though Highway 2 existed only a short distance to the north of Highway 73's northern terminus. Highway 73 and neighbouring Highway 74 are both strange anomalies of the Ontario provincial highway system, in that these two King's Highways ended at a county road junction and not at a provincial highway junction.

Highway 73 was entirely gravel-surfaced when it was first assumed. The highway was paved between Aylmer and the Springfield turn-off in 1938. Further paving work took place between Port Bruce and Aylmer in 1950, with the balance of the highway being paved in stages between 1952 and 1955. The entire highway was downloaded on January 1, 1998. The road is now officially known as Middlesex County Road 73 and Elgin County Road 73, although the road is still often referred to as "Highway 73" by motorists. Services are available in most communities along the highway. Unless posted otherwise, the speed limit on Highway 73 is 80 km/h (50 mph). Please visit the Highway 73 Mileage Chart page for a list of mileage reference points along Highway 73.