History of Provincial Highway 12A:
Provincial Highway 12A was one of Ontario's earliest highways, extending from the Trans-Provincial Highway (Highway 2) at Port Hope northerly to Peterborough.
In 1920, the Ontario government expanded the Provincial Highway System by assuming the Port Hope-Peterborough Road as a new Provincial Highway. Until 1925,
the highway was simply known as the Port Hope-Peterborough Highway. The road was assigned the designation Provincial Highway 12A when route numbers were
first introduced in 1925. Strangely, Highway 12A did not actually intersect with Highway 12 along its 47 km route.
In 1928, Highway 12A was renumbered as Highway 28. This made the Highway 12A designation the very first route number to ever be permanently retired from
the provincial highway system. Provincial Highway 12A was one of only two highways in Ontario that came into existence and disappeared entirely prior to the
changeover to the King's Highway designation in 1930. Highway 12A and the other route, Highway 4A, are thus the only highways in Ontario that were solely
known as a "Provincial Highway" and were not later designated as a "King's Highway".
Photographic History of Provincial Highway 12A
Learn More About Provincial Highway 12A
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