OS of N Ireland
Ordnance Survey (OS) of Northern Ireland is now part of Land & Property Services Northern Ireland. This is the agency responsible for mapping, land registration, valuation and rating in Northern Ireland. All Ordnance Survey of Northern Ireland branded products are now produced by Land & Property Services. OS of Northern Ireland, OS of the Republic of Ireland and OS of Great Britain have a shared tradition that goes back to the 1700s. The division into three separate institutions resulted from the partition of Ireland in the 1920s. The world's first large-scale mapping of an entire country was completed by OS of Northern Ireland in 1846. This was followed by an even more comprehensive survey in 1867.