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I downloaded a GML file of cities boundaries from Statistics Canada, but I can't make sense of them. For example, when looking at the boundaries for a city north of Toronto (Markham), the first coordinate pair in the list (gml:posList tag) is 7232029.8171445 964392.282857482.

It looks like the coordinates are in UTM format, but when I plug the numbers into a converter online to see them in long/lat using NAD83 and zone 17, it points to somewhere in the middle of the Atlantic Ocean.

The coordinates are accompanied by a PDF file that specifies the following geographic representation, but it still doesn't seem to help. I tried subtracting the false easting and northing values, but that doesn't result in proper coordinates.

  • Projection: Lambert conformal conic
  • False easting: 6200000.000000
  • False northing: 3000000.000000
  • Central meridian: -91.866667
  • Standard parallel 1: 49.000000
  • Standard parallel 2: 77.000000
  • Latitude of origin: 63.390675
  • Linear unit: metre (1.000000)
  • Datum: North American 1983 (NAD83)
  • Prime meridian: Greenwich
  • Angular unit: degree
  • Spheroid: GRS 1980

If anyone can provide some help on how to properly convert these numbers to long/lat it would be very helpful. I want to overlay them on a map in a custom application, so I can't just get the data in another format that's compatible with specific GIS apps.

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    Projection is EPSG:3347 (NAD83 / Statistics Canada Lambert).
    – TomazicM
    Apr 4 at 20:38

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The numeric values you are seeing are map coordinates but not UTM. The information you shared identifies the projection as Lambert conformal conic. This is EPSG:3347, known in QGIS as NAD83 / Statistics Canada Lambert.

Also documented on spatialreference.org

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