Urban mappings
A screendump from the GIS
One of the aims of the Chester project is to create a digital map of late-medieval Chester, showing in cartographic form how the city appeared on the ground at the end of the Middle Ages, say at around the time Henry Bradshaw was writing. Our approach to doing this is to combine in a GIS (Geographical Information System) Chester’s excellent surviving historic maps, and use these to selectively digitize certain urban features which were present in the city’s topography around 1500. There are problems with doing this – methodological issues that we hope we can resolve by doing the mapping work. Most obviously, in the period between 1500 and the date of the earliest accurately-surveyed and drawn maps made of the city (in 1850 by the Ordnance Survey), areas of Chester changed; in some cases quite dramatically. For this reason, we have to extract the city’s medieval topographic features from the different map sources available to us, and do so in such a way that we can identify which of the various historic maps we have used. Here GIS offers a great advantage, as within it we can tag all the digitized features with specific information about the sources used in this mapping process. In effect, this makes the map-making process more ‘transparent’, and allows users to track back how our modern map of medieval Chester was drawn.