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GIS at UCD and on the Web: Free OSI Data

UCD Library GIS Guide

Free OSi Mapping - Discovery Series Vector Tiles

Sample image of Discovery contour layer data in Irish Grid projection overlaid on Discovery mapping from MapGenie. Resolution: Contours: vertical interval of 10m. 

Discovery and Contour Data is available in vector format. Please download and complete the application form OSI Mapping Request Form - Discovery Vector and Contour Vector Tiles. 


Discovery Tiles Index

Discovery Series data at 1:50,000 scale is available in vector format in Irish Grid projection for the Republic of Ireland.

The Contour Lines data in Irish Grid projection for Discovery mapping is also available as a separate layer. 

This dataset consists of 10 metre contours for the Republic of Ireland.

Click on the Discovery Index above to find the tile (s) you need. Each of the 251 tiles which cover the country are represented on the squares above. Tiles for your area of interest are available to obtain by request by completing this application form and e-mailing to

For each square shown above two tiles can be supplied, e.g. 1838_C for the contour lines layer and 1838_D for the Discovery vector layer. Don't forget to ask for both!


Here's an enlarged extract from the index which shows you how to find the right tile number:

Use the Eastings along the bottom of the grid, followed by the Northings along the side to get your tile number.

Read the number on the vertical line at the left hand side of the square you need. Next, read the number on the horizontal line below the square you need. In this example above the square coloured blue is tile number 2408


Free OSi Mapping - Digital Data




Click on THIS LINK to sign in with your UCD Connect Account details and download the OSi Mapping Request Form - Vector Data .

Complete the section of the form relevant to you. Terms & Conditions for the use of the data are included at the end of the form on page 8 and must also be read and agreed and signed by the person requesting the data.  When completed the form should be scanned and e-mailed to

Applications received by e-mail during weekday working hours will be responded to within 48 hours.


Requests for Large Scale Vector Data are limited to 1 square kilometre in an urban area and 5 square kilometres in a rural area.

Click on this PDF to show a screen grab image of a 5 square kilometre area together with vector image of the same area.

Click on this PDF to show a screen grab image of a 1 square kilometre area together with vector image of the same area.

If you have data requirements outside of these restrictions please contact:


Historic 6 inch Colour 1st edition  1829 - 1842
Historic 6 inch B&W 1st edition  1829 - 1842
B&W Historic 6 inch  early to mid 20th century
B&W Historic 25 inch 1888 - 1913

Historical mapping as listed above is available as raster data in TIFF format. Please complete the application form OSI Mapping Request Form - TIFF Data which you can download from this link.

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