I have a shapefile map of Belgium divided by cantons that I want to re-project in order to have units in meters and to be able to calculate distances. I know how to do it with ArcGIS Projection tool, but the result always gets wrong map location.

I will detail my steps. First of all, my original map had unknown projection and coordinate system. However, it is pretty clear that it is in GCS_WGS_1984, with decimal degrees, since the Left/Top/Right/Bottom limits are precisely equal to the real ones of Belgium, when a map of this country is projected that way. So far, so good. I defined the GCS_WGS_1984 projection with DD units in ArcGIS, using the Define Projection tool.

The problem is in the next step. I then want to convert from that to another projection. One from which I can have units in meters. I tried a bunch of UTM options, using the Project tool after finding out that Belgium is around UTM 31N. However, no matter which UTM projection I choose, the location of the country after re-projected becomes wrong.

For instance, re-projecting from thw GCS_WGS_1984 to WGS_1984_UTM_Zone_31N gives me the following extent limits: Left:468861,233828 m; Top:5707355,258593 m; Right:742547,667605 m; Bottom:5485665,513781 m. That's very off the target.

Could anyone point me what am I doing wrong or what is missing?

PS: Another detail is the following. I tried opening the original map among other country maps with the GCS_WGS_1984 projection in decimal degrees. All countries are positioned correctly. Then, I do the same operation described above to convert some countries besides Belgium to check what happens. All of them get located wrong - what means, my problem doest not seem to be in my Belgium files, but rather in me doing something wrong.

  • What exactly is off target? is it the eastern boundries or western? Belgium is actually benn split to its east between UTM zone 31 and 32. Regarding other countries you've tried: did you use the right UTM zones? or tried it with zone 31 as well? In a brief the UTM projection should minimize distortion since of its division to zones. You might want to double check the origin of your data; is it possible the WGS84 isn't th source spatial reference? – dof1985 Mar 20 '15 at 7:28
  • Another thought - you might want to check your on-the-fly coord. system; it might be possible that it is stil rendering using the WGS84, which should distort your data view. Then if it doesn't help, I suggest to check some anchor points with manual conversion, you can use this site to accomplish this (uwgb.edu/dutchs/usefuldata/ConvertUTMNoOZ.HTM) – dof1985 Mar 20 '15 at 7:36
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    Please edit the question to contain the coordinate system string(s) that you have tried, along with the decimal degrees bounding box in GCS_WGS_1984. – Vince Mar 20 '15 at 14:25
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    Are you trying to match these up to a Web Mercator base map? If so, try using 3857 for the output coordinate system. – mkennedy Mar 20 '15 at 16:33

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