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I'm having problems with visualizing a layer which is in EPSG:4326

Apparently the geometry looks perfect, but I don't know why, it's not in real coordinates.

I have projected it to 4326 with QGIS, re-projected with ogr2ogr, and the result is always the same, the coordinates shown in the box while I pass the mouse are not real.

SRC of the project is in 4326, and 'on the fly' is set to on.

Any idea what could be happening? I attatch the europe roads layer, if anybody wants to open it and check for some issues.

Thanks a lot!

Shapefile: https://dl.dropboxusercontent.com/u/64621273/roads.rar

  • 2
    The projection information is wrong, the coordinates aren't EPSG:4326. EPSG:4326 is a geographic coordinate system, so the coordinates are latitude/longitude which can only range from -90:90 and -180:180. You have to contact the person who gave the data to you to find out what the actual projection is. – Jake Oct 18 '13 at 6:39
  • It's an official repository from the UN link I've been looking for some metadata but I don't find anything. Do you know if there are some way to project it to some plane CRS without knowing the actual projection? Thanks! – Pablo Pardo Oct 18 '13 at 8:10
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The first archive ("Roads Data - tables and layers") doesn't contain the projection information, which is pretty bad form. However, the second archive ("Roads ArcReader Projects") has the projection information in its .prj files:

PROJCS["Clarke_1866_Polyconic",GEOGCS["GCS_Clarke_1866",DATUM["D_Clarke_1866",SPHEROID["Clarke_1866",6378206.4,294.9786982]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Polyconic"],PARAMETER["False_Easting",0.0],PARAMETER["False_Northing",-2222408.5],PARAMETER["Central_Meridian",10.0],PARAMETER["Latitude_Of_Origin",33.0],UNIT["Meter",1.0]]

To fix your data, you can either create a text file called redfinal3.prj in the same directory as your .shp file and copy the code text from above into that file, or you can create a new custom CRS in QGIS with the following proj4 string:

+proj=poly +lat_0=33 +lon_0=10 +x_0=0 +y_0=-2222408.5 +ellps=clrk66 +units=m +no_defs
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    The choice of the second archive ("Roads ArcReader Projects") with the projection information included is the best choice, thanks! – markusN Nov 20 '14 at 22:16

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