The National Monuments Service is part of the Department of Arts, Heritage and the Gaeltacht. Among its functions is surveying and compiling inventories of sites of archaeological interest.
These data are stored in the Archaeological Survey of Ireland's Sites and Monumnents Record. They are available as paper maps and files and in digital form in a Historic Enviroment Viewer on the National Monuments Services Website.
The purpose of the National Inventory of Architectural Heritage is to identify, record and evaluate the post-1700 architectural heritage of Ireland as an aid in the protection and conservation of the built heritage.
The Historic Environment Viewer shows data from the Sites and Monuments Record of the National Monuments Service in red and from the National Inventory of Architectural Heritage in blue. It is a single resource for built heritage data for Ireland.
When you first access the site you see a map of Ireland.
In the top left of the screen there is a +/- zoom tool and a search box to find particular addresses and locations.
A series of icons appears to the right of the dark bar across the top of the screen. Hovering the mouse over each of these provides a description. The tools are as follows:
Query Data allows you to search for specific types of monuments from the Sites and Monuments Record of the National Monuments Service and the National Inventory of Architectural Heritage.
Layer List allows you to select data from the National Monuments Service, the National Inventory of Architectural Heritage or both.
Base Map Gallery allows you to select which underlying map the monument sites are shown on - OSI Map, Aerial, Cassini 6-inch, Historic 25 inch, Historic 6 inch, Digital Globe.
Locate allows you to search for a particular pair of easting and northing coordinates and choose the coordinate system: Irish Transverse Mercator, Irish National Grid, WGS 84
Data Export allows you to export the map data in a variety of formats for import into other systems.
Draw and Measure allows you to make some basic markings on the map
Print maps in the Yeats Library are held in a series of upright cabinets and plan drawer cabinets in the Infozone.
Most maps are listed and may be searched by keyword or other headings in the Library Print Catalogue. There are also lists and other information regarding the maps on the cabinets themselves. In addition to providing the title of each map, the lists on the upright cabinets indicate towns and other locations found on each map as a general guide to finding the location you require.
A summary of the Ordnance Survey maps in the cabinets is provided in the tabs Upright Cabinet 1 and Upright Cabinet 2
Note: In order to provide coverage of the island of Ireland as a whole with an integrated numbering system, the Ordnance Survey of Ireland and the Ordnance Survey of Northern Ireland use a continuous numbering system for their Discovery and Discoverer series.
The National Monuments Service have produced paper maps and indexes based on the Sites and Monuments Record. 
These maps are based on the Ordnance Survey of Ireland Maps with each archaeological site circled. The index allows particular sites to be searched by name. The Yeats Library has the majority of these maps and booklets in stock located in the Plan Drawer Cabinets in the Info Zone.They are also available in the Historical Environment Viewer.