The zones are numbered from 1 to 60 eastward, beginning at the 180th meridian. A grid system is superimposed on the zones, and separate Transverse Mercator projections are centred on each zone. An area containing a dense concentration of population. It must have a population of at least 1,000 and a density of at least 400 persons per square kilometre, based on the previous census. Urban areas are comprised of complete enumeration areas.
All territory lying outside urban areas is considered rural.
Taken together, urban and rural areas cover all of Canada. Digital Boundary Files pdf - good source for data descriptions and coding of datafiles for all datasets.