One of the most interesting and enjoyable activities at Ashford Castle was a boat tour of Lough Corrib aboard the 80-passenger Isle of Inisfree. The vessel’s exceptionally articulate and knowledgeable captain told us that the lake contains a trove of underwater archaeological sites, including several vessels from the Viking days, among them the well-preserved Carrowmoreknock boat. (Bronze spearheads and a rare wooden spear have been recovered for conservation by the National Museum of Ireland.) The most famous of Lough Corrib’s 1,327 islands is Inchagoill Island, midway between Cong and Oughterard.