From Wikipedia, the free encyclopedia
Jump to: navigation, search

Glencastle (Irish: Gleann Chaisil) is a village of about 30 people in the northwest of County Mayo, Ireland. The townland incorporates an area of 2,336 acres (9.45 km2).


Glencastle, Dún Domhnaill fort

Glencastle is a mountain valley which used to be known as the gateway to the Mullet Peninsula. Standing in the middle of this glen and guarding the gateway into Erris stands an ancient fort called "Dun Donnell" or the fort of Domhnall, who was, according to legend, of the Gamanraige tribe and an ascendant of an Ailill Finn the husband of Flidhais and deeply entangled in the tale of Táin Bó Flidhais. Standing by the old fort, the panorama of Broadhaven Bay and Blacksod Bay comes into view. As part of the cycle of Celtic folklore & legends, Domhnall used to close the gates of Erris at night levying tolls on passers-by. The remains of this once-great castle are now three very large mounds close to the road on the right hand side as you travel westwards, which have never been archaeologically investigated.


The O'Caithnaidhs, who were chiefs of Erris before the Norman Invasion in the 12th century AD, had their stronghold in Glencastle. They were defeated by the O'Connors who then took over the fort until 1303 when it was conquered by the Barrett Normans. In 1540AD the Barrett's castle in Glencastle was so well known that the English called Erris, 'Arrus Dundohmnaill'. For the next two hundred years, the Barretts wielded their influence in Church and civil affairs.

There are several earlier archaeological monuments recorded in this village, but with the landscape destruction of the 21st century, it is doubtful if these are still in existence. It is recorded by Patrick Knight, Engineer that when the Belmullet/Bangor road was being made in the 1820s, that they "unnecessarily destroyed the fine dolmen in the glen rather than divert the road a few feet to one side".

Thomas Johnson Westropp, a prolific purveyor of antiquities on the western seaboard, who visited the Erris area in the early 20th century wrote the following of Glencastle in 1911. "It is a beautiful spot, especially after the dreary dirve through barren moors from Crossmolina through Bangor. We suddenly dip into a stream runnel and, without preparation drop into a lovely wooded glen, at first so narrow that there is barely room for the road and the brook; we pass a regular brown dyke of volcanic rock and a thickly-wooded hillside, hovered over by hawks, and reach the more open valley, the "Gates of Erris'. In its centre a grassy moat-like mass of rock was upheaved by some remote eruption. The east face is covered with hazels and birch, the upper trees growing out of the side to keep the shelter of the fort rising over 90 feet above the stream. To the north, a great mountain swells up for 760 feet facing the glen and its keeper. A second mound, like an overturned boat lies further down the valley" Unfortunately, due to 21st century quarrying on a massive scale, this former 'beauty spot' is barely recognisable as the entire hillside on the left hand side as described above has been mechanically removed to the dismay of visitors to Erris.


  • Knight, Patrick. Erris in the Irish Highlands (1835) Dublin
  • McDonnell, Bishop, Diocese of Killala p. 46
  • Noone, Fr. Sean, Where the Sun Sets (1991) Kildare
  • O'Donovan, Ordnance Survey Letters Vol. 1. p. 157
  • Westropp, T. J. The Promontory Forts of Ireland. Vol. 49 Pt. 2 p. 137

Coordinates: 54°11′N 9°53′W / 54.183°N 9.883°W / 54.183; -9.883