By Bryn Coldrick (Archaeological Management Solutions), with contributions from Tom Cassidy and Paul O’Keeffe
A pillbox is a small, sturdy structure made from reinforced concrete with narrow openings (often referred to as embrasures or gun loops) that could be used to fire rifles or light machineguns through while giving some protection to soldiers inside. They served a dual purpose of watching over strategic positions such as roads, bridges and other important infrastructure, and as fixed machinegun positions to delay and disrupt an enemy attack. The earliest pillboxes as we know them were built by the Russians during their war with Japan in 1904–05, then by Germans on the Western Front during World War I, and the idea was later taken up by the British to protect their coastline during both World Wars. In the early years of World War II, almost 300 pillboxes were built in Ireland, and concentrations can be found in places of high strategic value, including the Curragh, the Boyne Valley and around the Shannon Estuary.
The focus of our research is a line of pillboxes extending roughly west from Askeaton in County Limerick, many of which overlook the Shannon Estuary and Foynes to the north/northwest, which we have dubbed ‘the Askeaton Cluster’. This cluster roughly forms a line c. 5.3 km long, running east from Mulderricksfield to Ballycullen and then northeast to Askeaton (Illustration 7). Nine of these pillboxes were known sites listed on the County Limerick Record of Protected Structures (RPS). Eight pillboxes not listed on the RPS were recorded during research and fieldwalking undertaken by Irish Archaeological Consultancy and the TII Project Archaeologist during the Environmental Impact Assessment (EIA) for the current Project. Three of these structures were identified in the subsequent Environmental Impact Assessment Report as significant elements of the built heritage of the area that would be affected by the road development. Another example was discovered when the hedges were being cleared in preparation for construction of the new road.
Subsequent research in the Military Archives in Dublin has uncovered a map depicting the locations of almost 70 ‘blockhouses’ (pillboxes) around the Shannon Estuary, half of which (35) were around Askeaton, though some of these are no longer extant (Illustrations 8 and 9).
An important aspect of the current research is local engagement which has led to the identification of 10 previously unrecorded pillboxes, bringing the current tally on the ground to 28 (24 extant pillboxes and the sites of four demolished pillboxes). Pillboxes were often built into hedgerows and embankments to deliberately conceal their location. Therefore, the detailed knowledge of local landowners and residents is sometimes critical to finding their locations.
Landowners and other local people are also sharing anecdotes and personal historical material with us, including photos of family members who served in the Local Defence Force (Illustration 10), and remain on the lookout for other pillboxes in the locality. By raising awareness of their historical and built heritage value, we have successfully mobilised the local community to identify, report, and help us record them, which we hope will ensure their preservation into the future. Very few pillboxes are recorded or protected in Ireland, making them vulnerable to being lost to future generations. The current work is showing that they are valued by local communities as an important part of our built heritage and as tangible expressions of the history of the State.
One of our primary research objectives is to try to understand why there are so many World War II (‘Emergency’-era) pillboxes in this area. Our research has included reviewing plans drawn up by the Irish Army in 1940 to counter a possible attack on neutral Ireland by Germany, as well as separate plans to counter a possible Allied attack which arose from a fear that the British could invade Ireland to seize and make use of our seaports and airfields. Askeaton was at the junction of three defensive lines identified as part of this military planning, and the dense cluster of pillboxes constructed around Askeaton in 1940–41 would have served as a network of defensive positions in the event of a seaborne invasion via the Shannon Estuary. There was the added threat of airborne invasion targeting the seaplane base at Foynes and the new airfield at Rineanna (now Shannon Airport), as well as the general possibility of enemy parachutists. The pillboxes were built to help protect this critical infrastructure as well as the hydroelectric power station at Ardnacrusha, and population centres such as Limerick City and Ennis (Illustration 9). The Askeaton Cluster straddles the railway line linking Foynes and Rathkeale and also protects the local road network (Illustration 8), both of which would be vital for quickly moving troops and equipment in by the regular army to reinforce the Local Defence Force volunteers.
The built heritage surveys being carried out by AMS as part of the road project involve surveying, documenting and mapping the pillboxes. We are examining the methods of construction, including carrying out excavations to see how deeply they are embedded into the ground and what sort of foundation they are on (Illustration 11). We are also undertaking viewshed analysis to determine and map the field of fire from the structures’ embrasures (openings), the areas of the landscape that are visible from each embrasure, and intervisibility between pillboxes. We are carrying out further historical research to better understand the Askeaton Cluster and its role in Ireland’s defence during World War II. Finally, the project team is continuing our engagement with the local community and landowners to record and document these small but significant structures which form such an important part of independent Ireland’s defence heritage.
We are bringing the results our research back to the local community through talks and publications (online and in print), while our technical reports and other outputs will ultimately be made available through the TII Digital Heritage Collections at the conclusion of the project. In the meantime, AMS archaeologist John Channing has used photogrammetry to produce 3D digital models of several of the Askeaton pillboxes which can be found on Sketchfab, and you can view a video titled The Forgotten Defenders: Pillboxes of the Shannon Estuary on the AMS YouTube channel.
Further Reading
Barry, M B & O’Byrne, J 2024 The Emergency in Colour: Ireland in Wartime. Gill Books, Dublin. French, N n.d. ‘World War II’. Meath History Hub (https://meathhistoryhub.ie/world-war-ii/).
Gray, T 1997 The Lost Years: The Emergency in Ireland 1939–45. Little, Brown & Co., London.
Kennedy, M 2008 Guarding Neutral Ireland: The Coast Watching Service and Military Intelligence, 1939–1945. Four Courts Press, Dublin.
Kerrigan, P M 1995 Castles and Fortifications in Ireland 1485–1945. The Collins Press, Cork.
Historic England 2023 ‘A Brief Introduction to Military Pillboxes’ (https://heritagecalling.com/2023/10/19/a-brief-introduction-to-military-pillboxes).
MacCarron, D 1999 Step Together! Ireland’s Emergency Army 1939–46 as told by its Veterans. Irish Academic Press, Dublin.
McEnery, J H 2006 Fortress Ireland: The Story of the Irish Coastal Forts and the River Shannon Defence Line. Wordwell, Bray.
Litton, H 2001 The World War II Years: The Irish Emergency an Illustrated History. Wolfhound Press, Dublin.
O’Halpin, E 1999 Defending Ireland: The Irish State and its Enemies Since 1922. Oxford University Press, Oxford.
Osborne, M 2008 Pillboxes of Britain and Ireland. The History Press, Stroud.
Pillbox Study Group (PSG) 2025 ‘Committed to the Study and Preservation of 20th Century United Kingdom and International Pillboxes and Anti-Invasion Defences’ (http://www.pillbox-study-group.org.uk).
Stout, G & O’Reilly, M 2000 ‘Pillboxes on the Boyne (1939–45)’, in Journal of the Old Drogheda Society, No. 12.
Stout, G 2002 Newgrange and the Bend of the Boyne. Cork University Press, Cork.