Carlow (kärˈlō) [key], county (1991 pop. 40,942), 346 sq mi (896 sq km), SE Republic of Ireland. The chief towns are Carlow, the county seat; Bagenalstown, on the Barrow River, which forms much of the western boundary of the county; and Tullow, on the Slaney River which crosses the county from north to south. The granitic uplands of the Blackstairs Mts. in the southeast are a conspicuous feature in an otherwise fertile lowland region. Grain and sugar-beet farming, cattle raising, and dairying are regional occupations. There are also flour-milling, malting, and sugar-refining industries. The trains from Dublin to Kilkenny and Waterford travel through Carlow. Organized as a county in the early 13th cent., Carlow was strategically situated on the southern edge of the English Pale. In the 13th cent. it had palatinate privileges.