Ontario Highway 503

Highway 503 was a provincial secondary highway in Ontario, Canada, that existed between 1956 and 1998. Between 1956 and 1963, the highway stretched from Kirkfield to Sebright, and then along the Monck Road from Sebright to Kinmount, entirely within Victoria County. In 1964, the route was extended to Highway 121 in Tory Hill along the route of Highway 500, which was removed from the network. Its total distance of 116.8 kilometres (72.6 mi) was downloaded to the various counties in which it resided. Today the road exists as:

Kawartha Lakes Road 45 (also known as Monck Road) is a municipally-maintained class-3 roadway located in the city of Kawartha Lakes, in the Canadian province of Ontario. The road crosses the entire city from west to east, passing through several unincorporated villages along the way, Sebright, Uphill, Norland, Dongola and Kinmount. The road runs in a predominantly east–west direction and covers a distance of 50.0 kilometres (31.1 mi), primarily rural geography. Its western terminus is Kirkfield Road (Kawartha Lakes Road 6), and its eastern terminus is the Bobcaygeon Road.

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