The Ordnance Survey
The Ordnance Survey (OS) was originally established in Britain in 1791, and in 1824 the Survey established its Irish headquarters in Dublin, in order to undertake the mapping and measurement of Irish townlands. The maps were drawn on a scale of 6 inches to one mile and published between 1833 and 1846. They were later revised on a county-by-county basis. More info >>

SVG Plugin
Our online maps will currently only work with the Internet Explorer browser (Version 5.5+) on Windows 98-XP PCs. You will need to download and install a Scalable Vector Graphics (SVG) plugin for your Web browser before you can access our maps. More info >>

Security setting in Internet Explorer
If you are having a problem with accessing the OS maps open Internet Explorer and go to Tools, Internet Options, Advanced. Go down to the end (to the 'Security' options) and make sure that the 'Allow active content to run in files on My Computer' is NOT checked (i.e. that the second option in 'Security' is left blank).

Semi-offline solution
The maps make use of thousands of tiled images whose file sizes are necessarily quite large. As some windows may require four such tiles to be downloaded at any one time, you will need to have broadband access to the Internet for ease of viewing. If you do not have broadband access, please click here for information on obtaining a CD of the tiled images which can be used in conjunction with this online application. More info >>

The 1842 Ordnance Survey Online Maps
When you have the SVG plugin installed, and do not wish to avail of our 'semi-offline' solution, Click here for the online maps >>

About our 1842 Ordnance Survey Historical Map Digitisation Project:
In July 2004 Clare County Library decided to build an Internet Geographical Information System for the users of Clare County Library based on the 1842 Ordnance Survey 6 inch maps of County Clare, make it available through the library’s website at http://www.clarelibrary.ie/, and integrate it with other online resources of Clare County Library. More info >>