Estersnow (Roscommon)

Share This:
not to be confused with Carraig Mac Dermott aka The Rock of Lough Key
not to be confused with Carraig Mac Dermott aka The Rock of Lough Key

Caisleán Mhagh Loirg aka Moylurg Castle (lit. Castle of the Plain of Tracks) situated on a rise of natural bedrock overlooking Clogher Lough. Almost entirely surrounded by water in ancient times, Moylurg stood in close proximity to the ecclesiastical settlement of Díseart Nuan (lit. Noone's Hermitage aka Disert Noone > Isertnowne > Eastersnow) with its Patrician church and holy well of Tubber Noone.

Moylurg was a McDermott castle with references from 1487 to 1617. It consisted of a triangular bawn (dims c. 77m N-S; 10m E-W at N; c. 30m E-W at S) with the castle at its north end. A circular corner tower (int. diam. 2m) stood at its south end. Moylurg Castle was positioned north-west of Estersnow and 140m directly west of the ancient standing stone of Cloghastookeen aka  'Clogh-na-Stuakeen' aka 'Clogh-Cam'. Crannog (man-made lake forts), cairn (rock mounds), barrow mounds and Fulacht Fia (burned mounds), souterrain and caves are also numerous in this historic area.  

On the opposite side of Clogher lake (SSW) stood Ballynahoogh Castle.  

In 1487 Baile na hUamha castle was demolished by Aodh Ruadh Ó Domhnaill (c.1461-1505) whose sons re-built it circa 1492. Ballynahoogh was plundered by the Earl of Kildare in 1512 and captured and destroyed by O'Donnell again in 1527. Gallowglasses were brought into Moylurg by Sliocht Eoghan in 1562 and Baile na hUamha castle was burned.

In 1600 the lands at Bally Clogher were held by Bryan McDermott. In 1617 the lands were held by Cormac Mac Dermot Roe. By 1635 Clogher had reverted to Brian Óg Mac Dermot who was the Chief of Moylurg 1603-36. [Mac Dermot 1996, 123-4, 142, 296, 456]. 

Magh Luirg an Dagda (lit. the plain of the tracks of the Dagda ) aka Moylurg, was an ancient Gaelic kingdom (from c. 956–1585) largely represented by the Barony of Boyle today. The Mac Riabhaigh (aka McGreevy) were Kings of Moylurg until 1255 when they were dispossessed by Clann Maelruanaidh (aka Mulrooney) – later known as Clann Mac Diarmada (aka McDermott). Queen Elizabeth's Composition of Connacht in 1585 brought an end to McDermott rule of Moylurg, and their territory was renamed the Barony of Boyle

By 1650, the old church at Eastersnow was in ruins and one must assume Cromwell's forces broke the castle of Moylurg. It is believed locally that stone from the castle was used to build Moylurg House circa 1790.  19th-century Moylurg referred to this particular gentlemans' seat in the townland of Clogher near Cavetown.  

By the time John O'Donovan inspected it in 1837  "The ruins of a castle on the top of the rock called Moylurg Castle" were noted and depicted in the 1837 edition of the OS 6-inch map. 

"Yesterday I traversed the parish called Easter-Snow, and ascertained the sites of two castles of which the sappers have taken not notice.  There are (1) The Castle of Moylurg, and (2) the Castle of Baile-na-hUamha, now called Cavetown, from a very remarkable cave near it.  

The Castle of Moylurg, of which the foundations only are now traceable, stood on a remarkable rock, which was anciently almost surrounded by water; it lies opposite the remarkable stone called Clogh-a-Stuakeen, and immediately to the right of the road as one goes from Boyle to the village of Croghan.  The people of that neighbourhood thought it was the celebrated “Castle of the Rock” but I have satisfied them that it could not be, as the Rock (or Carrig Mac Dermot), the very celebrated fortress of Moylurg, is always spoken of as a rocky celebrated fortress of Moylurg, is always spoken of as a  rocky island in Lough Key.  The situation of this on of this castle, on a rock nearly surrounded by water, has given rise to this mistake and thought it is locally called the Castle of Moylurg, I fear it would be an error to call it Moylurg Castle on the Ordnance Map.

The Castle of Baile-na-huamha or town of the cave (so called from a remarkable cave, which goes, according to vulgar tradition, all the way to Kesh Corran) was situated between the Lakes of Clogher and Cavetown, and within about seven perches of The Fish House.  But very slight traces remain now.  The tradition in the country is proved by the testimony of the Annals that there was a castle at Baile-na-h-umhach (Na hUmhaidh) which belonged to the branch of the McDermots, now vulgarly called the Bundoon family in consequence of their poverty and pride, and in contempt for their having lost the fertile plains of Moylurg."      [John O'Donovan 1837].


The remains of Moylurg Castle in Clogher (lit. a stony place) are still visible on the top of natural bedrock, within the demesne of Moylurg House.

[Compiled by Rua Mac Diarmada 2018]



  • 1. AFM - Annals of the kingdom of Ireland by the Four Masters from the earliest period to the year 1616, ed. and trans. John O'Donovan (7 vols., Dublin, 1851; reprint New York, 1966)
  • 2. ALC - The Annals of Lough Cé: a chronicle of Irish affairs, 1014-1690, ed. W.M. Hennessy (2 vols., London, 1871; reflex facsimile, Irish Manuscripts Commission, Dublin, 1939)
  • 3. Mac Dermot, D. 1996 Mac Dermot of Moylurg: the story of a Connacht family. Manorhamilton. Drumlin.


Magh Loirg/Moylurg | Ireland VIEW SOURCE
An Clochar/Clogher| Ireland VIEW SOURCE
Clogher | Historic Environment Viewer Ireland VIEW SOURCE
National Folklore Collection: Cavetown and Moylurg Ireland VIEW SOURCE
Map of ancient Moylurg castles | Ireland VIEW SOURCE

Type of Building:


Some communities associated with this building

Some ancestors associated with these communities

Some buildings associated with these communities