Aughanduff is a small village and townland in the civil parish of Forkhill, in the former barony of Orior Upper, and County of Armagh, Northern Ireland. The townland is roughly co-existent with Upper and Lower Aughanduff Mountains, both of which form part of the Ring of Gullion geological formation, which has been described as the most spectacular example of a ring-dyke intrusion in Ireland or Britain, and was the first ring dyke in the world to be geologically mapped. Aughanduff has been populated since prehistoric times and has been recorded as a distinct district since at least the early 1600s. The area's history is both well documented and reflects its location both in rural Ireland and on the borderlands of the Pale, the Plantation of Ulster, and latterly Northern Ireland; indeed, part of the district's northern boundary was proposed for forming part of the northern border of the Irish Free State by the Irish Boundary Commission in its final report of 1925. The Boundary Commission's report was never implemented and today, the area remains within Northern Ireland, some five miles from the border with the Republic of Ireland. Part of the area has been designated by the Northern Ireland Environment Agency as an Area of Special Scientific Interest, and the district lies within the Ring of Gullion Area of Outstanding Natural Beauty.