Middletown is a small village and townland in County Armagh, Northern Ireland. It lies near the border with County Monaghan, between Arma…Middletown is a small village and townland in County Armagh, Northern Ireland. It lies near the border with County Monaghan, between Armagh and Monaghan along the A3. It had a population of 237 people in the 2011 census.