²⁹Harbison, Peter. Pilgrimage in Ireland: the Monuments and the People. Syracuse, NY: Syracuse Univ., 1992. 196.
Harbison here states, "The Glencolmcille pillars are unlikely to have acted as gravemarkers and were almost certainly erected in connection with pilgrimage activity in the valley." However an earlier publication he states, "The most conspicuous remains of this monastery are the pillars decorated with cross-motifs and geometric designs which may originally have been grave-slabs, but are now the centres or 'stations' of the pilgrimage..." Harbison, Peter. Guide to National and Historic Monuments of Ireland: including a Selection of Other Monuments Not in State Care. Dublin: Gill and Macmillan, 1992. 68.