Dublin, a maritime county, in the province of Leinster, is bounded on the north by Co. Meath, on the east by the Irish Sea, on the south by Co. Wicklow and on the west by counties Kildare and Meath. Its greatest length from Kippure Mountain on the south to the Delvin River near Balbriggan is 32 miles; and its greatest breadth from Howth Head to Clonee near Lucan is 18 miles