The Trans-Canada Highway between Victoria (BC) and St. John's (NF) is the world's longest national highway with a length of 7,821 km (4,860 mi.)
Although there does not appear to be any nationally sanctioned "starting point" for the entire Trans-Canada Highway system, St. John's has adopted this designation for the section of highway running in the city (down to the harbourfront) by using the term "Mile One" for its sports stadium and convention centre complex, Mile One Centre.
At the ohter end, the Victoria terminus of the Trans-Canada Highway, located at the foot of Douglas Street and Dallas Road at Beacon Hill Park, is marked by a "mile zero" monument.
Canada and the Trans-Canada Highway have been metric since 1977, so everything should maybe reference kilometer zero. Or we conclude metric conversion is messed up if the distance from "Mile Zero" to "Mile One" is roughly 8,000 kilometres.
The midpoint of the Trans-Canada, marking halfway along its journey from the Atlantic to the Pacific is at a market at Batchwana Bay, north of Sault Ste Marie, ontario.
The western endpoint of the Trans-Canada highway IS NOT IN TOFINO. This plaque was placed overlooking the Pacific Ocean by the town council of Tofino back in 1909, to spur the construction of the Trans-Canada Highway. They had the vain hope that the highway would go from the eastern shore of Canada (which at that time did not yet include Newfoundland) to the westernmost point along the Pacific (which even today, is not Tofino).
Instead, in the 1950s, the planners and politicians (along with the accountants figuring out the costs) decided to build the highway to connect major population centres across Canada (notably, skipping Toronto, which IS NOT on the Trans-Canada).
In British Columbia took the shortest ferry ride to the Island from Vancouver to Nanaimo, and then turned south to the provincial capital of Victoria, instead of veering west to Tofino. The road to Tofino remained a little-used logging road, and did not get paved until over a decade later.