Figure 1
Purgatory at Lough Derg. Photo: © Kenneth Allen, CC BY SA 2.0.
Figure 2
A pilgrim praying on St. Brigid’s Chair. Photo: Philip Dixon Hardy, The Holy Wells of Ireland: Containing an Authentic Account of Those Various Places of Pilgrimage and Penance Which Are Still Annually Visited by Thousands of the Roman Catholic Peasantry. With a Minute Description of the Patterns and Stations Periodically Held in Various Districts of Ireland (Dublin: Hardy and Walker, 1840), public domain, out of copyright. Altered colour to improve visibility due to yellowing of paper in digitisation.
Figure 3
Down Survey Map for Barony of Tirhugh, County Donegal, ‘An Island unto which the Papist did come a Pilgrimage’. William Petty, A book containing a generall map of Ireland with the lower provinces and countyes thereof (1655–6). Photo: Bibliothèque national de France, public domain. DOI: ark:/12148/btv1b52509533x.
Figure 4
Satellite Image of Lough Derg. Photo: Google Earth, Image © DigitalGlobe, via Google reuse policy.