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Lake · Clonbur

Lough Mask

Clonbur sits on the neck of land between two great lakes, and the northern one is Lough Mask. It covers about 83 square kilometres across the Galway and Mayo line, the fourth largest lake in Ireland, and its water leaves not by a river but through the Cong Canal and passages in the limestone, joining at Cong to form the short River Cong into Lough Corrib. The eastern half is shallow and full of islands; the western half sinks into a trench more than fifty metres deep.

Checked against the source on 2026-09-19.

Jetty on Lough Mask Jetty and picnic area to the north of Toormakeady on Lough Mask.
Jetty on Lough Mask Jetty and picnic area to the north of Toormakeady on Lough Mask.
Oliver Dixon, CC BY-SA 2.0 via Wikimedia Commons

Lough Mask, Loughmask Castle, Ashford castle on the 3D model; tap a pin for its page and directions.

Burkes and the Land War

In 1338, at the end of the Burke civil war, Sir Edmond de Burgh was captured at Ballinrobe by his cousin Sir Edmond Albanach Bourke, taken to the Earl's Island and drowned in the lake. A note in the oldest manuscript of the Pursuit of Diarmuid and Gráinne records the scribe Dáibhídh Bacach Ó Duibhgeannáin living on Oileán Ruadh, the Red Island, in the house of Tadhg Óg O Flaherty on 1 April 1651. The Lough Mask Murders of 1882 were a notorious episode of the Land War. Local legend gives Bly Island a banshee.

Trout and boats

The lake is famous for trout, and the World Cup Trout Fly Fishing Championship is held each year at Cushlough Bay near Ballinrobe. Petersburg Outdoor Education Centre on the shore near Bly Island uses the water for kayaking, canoeing and sailing. Séan Seoighe took Loch Measca as his pen-name for his memoir Eachtra Múinteora in 1929. The model on this page pins the lake and Loughmask Castle; Ashford Castle and Cong Abbey, at the other end of the canal, have their own guides.

Questions people ask

How deep is Lough Mask?
The mean depth is 15 metres; the western trench goes beyond 50 metres.
Where does Lough Mask drain to?
Through the Cong Canal and underground passages in the limestone into the River Cong and Lough Corrib.
Is Lough Mask good for fishing?
It is known for trout and hosts the World Cup Trout Fly Fishing Championship at Cushlough Bay every year.

Written from Wikipedia, "Lough Mask" (CC BY-SA 4.0), read on 2026-09-19, and from the OpenStreetMap places on the model. Nothing has been added from memory; follow the source for its footnotes.