Causeway Coast Holiday

Attractions

Wider Northern Ireland

Castlederg Castle, County Tyrone

Fact-checked 20 August 2026

One date contradiction flagged, not resolved, in this pass - see notes above. Castlederg Castle, a ruin on the River Derg estuary in County Tyrone, sits within Derry City and Strabane District Council (the current local authority since 2015 - not the former, separate Strabane District Council named in earlier versions of this page).

History

The site’s history is genuinely layered: an earlier O’Neill tower house stood here before Sir John Davies, an English commissioner granted 2,000 acres by King James I, built the castle whose ruins remain today. The castle changed hands repeatedly between the O’Neill and O’Donnell clans, was used as a refuge for planter families during the 1641 rebellion, and was ultimately besieged and rendered unusable by Sir Phelim O’Neill’s forces during that same rebellion.

Local legend holds that a tunnel once ran from the castle beneath the River Derg - the “Castle Hole” - supposedly collapsing on a piper who played to mark his progress while escaping through it. This is presented as folklore, not verified history.

Architecture

The ruins comprise a rectangular bawn (defensive wall) with square corner towers - riverside towers open-topped for artillery, north-side towers roofed as living quarters - a design typical of the Plantation era.

Things to Do

Nearby: the Druid’s Altar and Todd’s Den, two ancient tombs; the annual Dergfest Music Festival; and the long-running Apple Fair. The Castlederg War Memorial honours local residents lost in the World Wars.

Related guides

← Back to Attractions