Possible Duplicate:
Identifying Coordinate System of Shapefile when Unknown?
Are there any tools to help retrieving the projection system used to create a shapefile when there is no .prj file?
Given that there are well-known projection systems and that most of them deal only with a small area of the earth, it may be possible to find the projection system or just to reduce the possible candidates by providing information about the data extents. Also, overlaying the data on a map with a known projection system can help to guess the projection system by manually trying them to find one which match.
Does a tool exist to do that?
