Ecclesiastical Ruins on Inniscaltra, or Holy Island, Lough Derg, Co. Galway, after Sunset: 'This Island is One of Great Historic Interest ...' Petrie (c. 1863). Watkins, Bartholomew Colles 1833-1891. Inniscaltra, also called Holy Island, is one mile south-east of the village of Mountshannon, in the stretch of Lough Derg which is situated in Co. Clare (not in Co. Galway, as stated in the title). The monastery on the island was founded by St Caimin in the seventh century but was burned by the Vikings in 836 and 922 AD; however, St Caimin?s church continued in use until the fourteenth century. Buildings remaining include five churches, an anchorite?s cell and a round tower. Watkins specialized in Irish mountain scenery, such as in the Killarney area and monastic ruins and castles in various parts of the country. His works are simply and realistically executed, with a strong feeling for light; witness the magnificent sunset effects of this painting. The work was shown at the Royal Hibernian Academy in 1866, as was another version of the picture, the whereabouts of which is unknown.