Analysis of information sources in references of the Wikipedia article "Autoestrada" in Portuguese language version.
The key high-volume highways in Ontario are the 400-series highways in the southern part of the province. The most important of these is the 401, the busiest highway in North America, with average annual daily traffic (AADT) of more than 425,000 vehicles in 2004 and daily traffic sometimes exceeding 500,000 vehicles.
