The county of Northern Ireland is composed of three distinct areas: Antrim, Armagh, and Londonderry. Antrim is a county in the northeast of Northern Ireland, bordered by the North Channel, the Irish Sea, and the Atlantic Ocean. Armagh is a county in the south of Northern Ireland, bordered by the River Blackwater and the River Bann. Londonderry is a city in the northwest of Northern Ireland, located on the banks of the River Foyle. All three areas are part of the United Kingdom and are considered to be part of Northern Ireland.