Souterrains in Ireland

A map of Souterrains in the Rep. of Ireland based on data from the National Monuments Service.

"A feature often found in ringforts is an underground passage or souterrain (popularly known as a cave or tunnel). They are usually built of stone but can also be tunnelled into rock or compact clay or gravel. Souterrains are sometimes found apparently independent of any enclosure and are also found in Early Christian ecclesiastical enclosures. They were used as places of refuge and possibly also for storage and can be encountered unexpectedly during loughing, bulldozing or quarrying. These structures can be unsafe, especially if recently uncovered and should be treated with extreme caution."

From the Irish Field Monuments handbook by the Department of Environment, Heritage & Local Government.

Sorry I don't have the data to hand for Northern Ireland. I was mainly curious about their distribution around the wider Tipperary area.

Souterrains in the northern portion of Ireland with the underlying geology.

It seems to suggest broadly that the underlying geology plays a big factor in where they are located. I think the underlying geology may also have been a factor in the location of some of the county boundaries also.

Souterrains in the southern portion of Ireland with the underlying geology.

They may be tricky to read because of all the different soil / geology types represented.

The maps are based on information from the National Monument Service of Ireland, Department of Communities - Northern Ireland Sites & Monuments Record, the Geological Survey of Ireland & Open Street Map Ireland contributors.