Meath (mēth, mēħ) [key], county (1991 pop. 105,370), 903 sq mi (2,339 sq km), E Republic of Ireland. The county seat is Navan. The land is mostly level, being a part of the central plain of Ireland, with extensive fertile areas near the Boyne and the Blackwater, the principal rivers. There is a sandy coastline of some 10 mi (16 km) along the Irish Sea. Grain and potato cultivation and cattle raising support the bulk of the population. Manufacturing exists in the larger towns. The region is important in Irish history. Tara was long the seat of the ancient high kings of Ireland. Meath was considered a fifth province of Ireland for many centuries and was not finally organized as a county until the 17th cent. Remains of archaeological interest have been found in the Newgrange mounds.