LOUTH, a maritime county in the province of Leinster, Ire land, bounded north-east by Carlingford bay and Co. Down, east by the Irish sea, south-west by Meath, and north-west by Mona ghan and Armagh. It is the smallest county in Ireland, its area being 202,731 ac. or about 317 sq.m. Pop. (1926) 62,687.
Much of the county is occupied by an undulating lowland of much-folded Silurian shales and fine-grained sandstones; but Carboniferous Limestone overlies these rocks north and east of Dundalk. Igneous rocks form a mountainous promontory, ap proaching 2,000 ft. in height on the border of Carlingford lough. A raised beach provides a flat terrace at Greenore. As in the adjacent parts of Armagh and Monaghan, lead is worked.
Apart from the promontory of Clogher head, which rises abruptly to 180 ft., the coast is mostly low and sandy. Carlingford lough is navigable beyond the limits of the county, and Carling ford and Greenore are watering-places on the Co. Louth shore.
The Bay of Dundalk stretches to the town of that name and affords convenient shelter. The principal rivers, the Fane, the Lagan, the Glyde and the Dee, flow eastwards. The Boyne is navigable for large vessels as far as Drogheda.
The territory which afterwards became Co. Louth was in cluded in the principality of Uriel, Orgial or Argial, which em braced also the greater part of Meath, Monaghan and Armagh. The chieftain of the district was conquered by John de Courcy in 1183, and Louth or Uriel was among the shires generally con sidered to have been created by King John, and peopled by Eng lish settlers. Until the time of Elizabeth it was included in the province of Ulster. The cromlech of Ballymascanlan lies be tween Dundalk and Greenore. Danish raths and other forts are numerous. The most interesting monastic ruins are at Monaster
boice and Mellifont, both near Drogheda. At the former site are two churches, the larger dating probably from the 9th century, the smaller from the 13th ; a round tower, Ito ft. high, and three crosses, two decorated. At Mellifont are the remains of the first Cistercian monastery founded in Ireland, in 1142, with a gate house, an octagonal baptistery and chapter-house. Carlingford and Drogheda have monastic remains, and at Dromiskin is a round tower, in part rebuilt. Ardee, incorporated in 1376, has a 13th century castle. At Dunbar a charter of Charles II. (1679) granted the right to elect a sovereign. Louth, 5 z m. S.W. from Dundalk, gave its name to the county, and contains ruins of an abbey to which was attached one of the most noted early schools in Ireland.
In the lower regions the soil is a rich deep mould, adapted for cereals and green crops. Agriculture generally is in an advanced condition, and the farms are well drained. Oats, barley, flax, po tatoes and turnips are cultivated. Cattle, sheep, pigs and poultry represent the bulk of the live stock. Linen manufactures are of some importance. The deep-sea and coast fishery has its head quarters at Dundalk, and the salmon fisheries at Dundalk (Castle town river) and Drogheda (River Boyne). The county is tra versed by the Great Northern railway; while Dundalk is con nected with Greenore by the L.M.S. railway. From Greenore passenger steamers run regularly to Holyhead. Ardee is served by a branch from the Great Northern line at Dromin. Louth returns three members to Dail Eireann.