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I have a scanned image (tiff) of a historic map, with no information of the used coordinate system, which I want to georeference, to finally be part of a WebMap application with Leaflet.

As far as I know, for WebMaps the coordinate reference system is the "WGS84 Web Mercator (Auxiliary Sphere)". Due to that, I thought it would be best to georeference it directly to the used coordinate system.

My approach would be to georeference the historic image using an ArcGIS basemap.

My constraints are that ArcGIS basemaps do not have the best resolution, and I am worrying about the accuracy of georeferencing. What I could do is to include some vectors of topographic features (rivers, streets, lakes) to increase the accuracy, but I am not sure if this is a valid way to do.

Is it recommended to georeference based on ArcGIS basemaps or could you suggest a more appropriate approach?


The historic map is a topographic map, it shows landscape features and in addition old paths. These paths should be digitized, after the map is georeferenced, to create a WebMap with Leaflet showing users where to walk on "old paths".


I tried to georeference by mountain ranges, that could be seen on the historic map as well as on the basemap (although I am not sure in which quality these are represented on the basemap) and by river crossings which still exist. Just to clarify, I did not use the course of the river itself, but only intersecting points of two or multiple streams that are still valid.

I am georeferencing using ArcGIS Desktop.

  • Are you georeferencing using ArcGIS Desktop or something else? There are many options for what can be used as control points when georeferencing. The key criteria is that they are accurate enough for your purposes. What have you tried and were the results OK? – PolyGeo Mar 23 '17 at 20:53
  • Yes I am georeferencing using ArcGIS desktop. – the_chimp Mar 24 '17 at 18:59
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It really depends on the topic of the historic map. As a general rule, try to look at what kind of control points (to ground truth) you can achieve with what's on the map itself and what is likely to have not changed much from the historic map to the current day.

I would recommend using vector data first like your suggestion of streets if you have them as a starting point. Road centre lines or road edges often don't change drastically in some areas.

I would be wary of using watercourses for geo-referencing as these not only change seasonally but also change quite drastically over time. Also try using an aerial photography if you have access and look for similarities too.

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