Revised instructions for using the ITM (Irish Transverse Mercator) coordinates given for various historic locations on this website to show locations on Historic maps on the Ordnance Survey Ireland GeoHive website (updated November 2024) :
1. Copy the ITM coordinates, e.g. 717528,731612 on the required page, e.g. Catholic Parish Links, Church of Ireland Parish links or Coastguard station pages.
2. Open the OSI Geohive map viewer in a browser and accept the terms of use option.
3. Select the ‘Search option to the top left of the page – ‘Find Address or Place’ and paste or type the ITM coordinates followed by :2157 and press return/enter (:2157 is the code for ITM Coordinates). A search can also use Latitude/Longitude coordinates (GPS) in decimal format, e.g. 53.32169, -6.23586
4. The selected location is shown on the modern OS map
5. Click the layer option button top left (marked in red) and select the ‘Historic 6″ First Edition Colour’ maps to show details from about 1840, you may need to zoom out a little to show the map (buttons top left marked in blue), the Historic 25 ” maps date from c1900.
6. Location of Chapel marked on c1840 map – Donnybrook old RC chapel.
[previous version for old GeoHive/OSI system for reference only]
1. Open the GEOHive map viewer (opens in a new tab/window), and select ‘Data Catalogue/Base Information and Mapping’ option on the top left, and scroll down to the ‘Historic Map 6 inch Colour (1837-1842)’ or ‘Historic Map 25 inch (1888-1913)’ and select using the adjacent checkbox.
2. Return to the page on this website, e.g. the Catholic Parish details and copy the ITM coordinates of the Chapel. ITM coordinates consist of two six digit numbers referred to as Easting and Northing separated with a comma, and paste these into the search option at the top of the GEOHive page, and press enter.
3. GeoHive should select the correct location and zoom in, with a red marker at the location. Drag the the transparency option to the right to show only the historic map.
4. Some location details only show on the later maps. Note the older maps cover most of Ireland, but the later 25 inch maps do not have good coverage of counties now in Northern Ireland.
GeoHive also allows searches by placename, and using decimal Latitude/Longitude coordinates – e.g. ‘53.293309, -6.224867’.