ARRANMORE, an island, in the parish of TEMPLECROAN, barony of BOYLAGH, county of DONEGAL, and province of ULSTER, 3 miles (W. N. W.) from Rutland 5 containing, in 1834, 1141 inhabitants.

This is the largest of a group of islands called the Rosses, lying off the north-west coast, about two miles from the shore, in lat. 54° 51' 45" (N.), and lon. 8° 31' 45" (W.): it is three miles in length and three in breadth, and is about nine miles distant from the mainland; comprising, according to the Ordnance survey, 4355 statute acres, of which about 650 only are under cultivation and in pasture, and the remainder is rugged mountain.

In 1784 a large herring fishery was carried on successfully on this part of the coast, in which 400 sail of vessels and about 1000 small boats were employed; but within the last thirty or forty years it has been entirely discontinued.

On the north point of the island, which is a large rock of granite, was formerly a lighthouse, fitted up with an improved apparatus in 1817 by the corporation for the improvements of the port of Dublin, which has since been removed to Tory Island; the house remains, but is not lighted.

There is good anchorage on the east side of the island in an open roadstead. In the R. C. divisions this place forms part of the parish of Templenane or Templecroder, in which is the chapel, where divine service is performed every third Sunday.