New Castle, Delaware
Community History and Archaeology Program
Overlay of c1680 and 2008 parcel maps
(Overlay of a composite of the Heite 1680 maps (black)
over 2008 tax parcel map
) Click on map to see enlarged full map. Courtesy Louise B. Heite
Overlays allow easy visual of similarities and differences between New Castle now, and 300 years ago.
Click on areas B, C, E, H, J, K in the sketch map to see the overlays in
the box above.
When all 9 maps from Louise Heite were assembled into a composite, and
overlayed on county parcel maps it becomes apparent how
little has changed for the block and street layout in the center of town.
The same is not true for population density. Most parcels have been subdivided into two or many more smaller parcels.
For example in block E (between Delaware, Harmony, Strand and 2nd), the single
parcel E-X running along Harmony between the Strand and 2nd has been subdivided into 8 parcels.
Individual overlays were not created for areas A, G, or F, either because there were too
few control points for alignment (A, F), or it was not clear where the overlay should be placed.
This problem can be avoided with and overall view made by assembling all the individual maps since they
are done at the same scale.
Though less accurate for individual blocks, the combined map overlay
does confirm that the overall plans in 1680 and 2008 are similar.
How the overlays were made
The Heite maps were combined with New Castle County
tax maps by 'georeferencing'
using ESRI ArcGIS software. This involves
choosing pairs of control points on the Heite map and the tax map, then rotating, scaling or shifting the
Heite map until
the difference between each set of control points reaches a minimum. These control points can be seen
of the maps as blue crosses.