Promontory fort

Situated at the tip of a low triangular headland in an area of poorly drained rough grassland and scrub along the N shore of Achill. The site is overlooked by gently rising ground to the S. The view from the site is panoramic and the fort is surrounded by sheer cliffs on three sides. Unmarked on any OS map and was described by Westropp (1914a, 304-5) who called it 'Porteen', after a nearby cove. A broad north facing headland measuring 27m E-W by 12m N-S is defended by two curving banks and ditches. The inner bank is round topped and steep sided along the west becoming less clear towards the W. It averages 4m to 5m in width and 1.2m high above the ditch. It is 0.4m higher than the level of the interior and has no entrance gap. A shallow flat bottomed ditch runs along the outer edge of the bank. It averages 3m in width and slopes gently down to the W. It is waterlogged at the eastern end where its inner edge becomes indistinct. A faint rise in the base of the ditch near the western end suggests a causewayed entrance. The 5m wide 0.5m high earthen outer bank diminishes to 3m at either end. It is round topped and though several large boulders can be seen in its make-up, there is no trace of any revetting. A 1.4m wide breach 8m from the western end corresponds to the rise in the inner ditch and may be the remains of a causewayed entrance gap. The eastern edge of this bank was disturbed by a later field fence. The outermost ditch is wet and shallow, being only 0.3m below the outer ground level. It is visible mainly as a 2m wide band of dark vegetation and was disturbed at either end by later field walls. The wet interior of the site is featureless except where some undulations where scraw has been removed. It slopes gently down to the east. These descriptions are derived from the MA thesis of Markus Casey 1999 The coastal promontory forts of Ireland. A survey of counties Sligo, Mayo, Galway and Clare. Unpublished MA thesis, National University of Ireland, Galway. Date of upload: 5 December 2018