INNISCALTIIRA, or INNISKELTAIR, or HOLY-ISLAND, an island, in that part of the parish of INNISCALTHRA, which is in the barony of TULLA, county of CLARE, and province of MUNSTER, 4 miles (E.) from Scariff. This island, which is also called the "Island of the Seven Churches," is in Lough Derg, between the counties of Clare and Galway. St. Camin, who died about the middle of the seventh century, founded an abbey or church here, which was afterwards called Teampul Gamin. In 834 the island was ravaged by the Danes from Limerick, and in 1027 the great Brien Boroimhe rebuilt the church. St. Cumin, the founder of the abbey, is said to have written a commentary on the Psalms, which he collated with the Hebrew text. St.
Coelan wrote a life of St. Bridget iu Latin verse; and Corcran, the most celebrated ecclesiastic of Western Europe for religion and learning, was abbot, in the early part of the eleventh century. Here are the remains of seven small churches, which display considerable elegance of design. Here is also an ancient round tower in very good preservation, which is likewise called the Anchorite's Tower, from St. Cosgrath, an anchorite, having lived and died in it in the tenth century. This island is still a favourite burial-place, and is much visited by pilgrims. It contains about 25 acres of very rich land, and in its vicinity are Red Island and Bushy Island.
from Lewis's Topographical Dictionary of Ireland, 1837.