Republic of Ireland–United Kingdom border

The Republic of Ireland–United Kingdom border, sometimes referred to as the Irish border or British–Irish border, runs for 499 km (310 mi) from Lough Foyle in the north-west of Ireland to Carlingford Lough in the north-east, separating the Republic of Ireland from Northern Ireland. Border markings are inconspicuous, in common with many inter-state borders in the European Union.