PM-14_Historic-DataBetween 1829 and 1842 Ordnance Survey Ireland completed the first ever large-scale survey of an entire country. Acclaimed for their accuracy, these maps are regarded by cartographers as amongst the finest ever produced. As the national mapping archive service for Ireland, OSi has captured this and later mapping data in a digitised format. These maps are particularly relevant for genealogy or those with an interest in social history.