Local History by Seán Beattie


The Vallum at Carrowmore Monastery

The recent discovery of a wall belonging to the monastery at Carrowmore has raised the issue of comparisons with Nendrum monastery in Islandmagee. H.C. Lawlor mapped an inner trench or vallum and an outer trench here in 1925 and refers to another at Iona. The site at Iona has been destroyed as the original buildings were originally of clay and wattle. Significantly he raises the question as to whether the site at Nendrum was originally an ancient fort dating from the fifth century and which the monks occupied when they established a monastery. Similar questions may be raised about Carrowmore following the research of the Bernician Studies group from Sunderland led by Max Adams and Colm O’Brien. The maps of the site which they produced appear to suggest the presence of an inner and outer trench or vallum embracing both High Crosses, sliced through by a secondary road.  The range of pre-historic remnants within a few square miles at Carrowmore point to the site and surrounding area as one of great importance in pre-Christian times and there is a strong possibility, based on evidence in the environment that Carrowmore was originally the site of an ancient circular fort. Bocan Stone Circle was the primary place of worship and celebration in pagan times and the two court tombs nearby looked after the  dead. 

Lawlor goes on to describe life within the monastery with the abbot’s house the centrepiece situated on high ground. The site has a well as has Carrowmore. As monks lived here, there was an extensive refectory and church. Lawlor speculates on the diet, suggesting fish, oysters and salmon. The monks at Carrowmore certainly had salmon on their tables as the Culdaff river was once the richest in the Foyle waters system. The level of the river was probably several feet higher than today and there is every possibility that it was navigable as far as the monastery from the sea. Evidence of the drop in water levels in Inishowen was dramatically revealed ten years ago by Newcastle University at Inch island where a line of oyster shells was discovered three feet above the present water level. For more information on Nendrum, see THE MONASTERY OF ST. MOCHAI OF NENDRUM by H.C. Lawlor, Belfast N.H.and P. Society, 1925. 


  1. brian Lafferty

    This is fantastic, the monastery at Carrowmore and the nearby archaeological sites of interest such as the Temple of Deen,Bocan stone circle and others deserve this extensive investigation. I think there’s a lot more to come from this extremely rich archaeological area. Credit to Sean,university of Sunderland,landowners etc for their hard work and research so far.

    • Comment by post author

      Small scale excavations have unearthed new information about the structure of the site, its importance as an industrial location for iron-working, opening up the possibility that the monastery was situated in a double ringed ancient fort. The links to Lindisfarne, Iona and Derry through Colmcille, Oswald, Aidan and O Brolachain are well established.

  2. Excellent talk in McGrory’s last night – great turn-out demonstrating the interest in history and heritage

  3. Dave

    Nendrum Monastery is located at Mahee Island, outside Comber, County Down. Not Islandmagee as stated.

Leave a Reply