General information on Georeferencing Georeferencing historic
maps involves using control points to attach coordinates to the
maps, thus defining their physical locations on the earth. This
links the map to a coordinate system and projection so that it
can be viewed alongside (or on top of) current maps or other
historical maps. The Georeferencing Process Georeferencing
involves the following steps: - establishing control points on
the map - attaching known geographic coordinates to each control
point - choosing a projection and coordinate system for the map
- increasing accuracy by reducing the differences between the
actual and program-predicted coordinates of control points For
North Carolina Maps, this process generally involves finding a
current, previously georeferenced map of the area covered by the
historic map. We found many of these maps as shapefiles through
TIGER/Line or through the NC Department of Transportation's GIS
Unit. Some towns and cities also have their own GIS units
offering georeferenc