Topographic maps produced by NRCan conform to the National Topographic System (NTS) of Canada. They are available in two standard scales: 1:50 000 and 1:250 000. Each map in this system has a unique number, which is a combination of numbers and letters. The area covered by a given mapsheet is determined by its location in Canada. To understand the numbering of these maps, refer to the National Topographic System Index Maps.
