Castlederg Castle, or Derg Castle

Castlederg (earlier Caslanadergy, from Irish Caisleán na Deirge, meaning 'castle on the Derg') is a town in County Tyrone, Northern Ireland. It lies on the River Derg and is near the border with County Donegal, Ireland. It stands in the townlands of Castlesessagh and Churchtown, in the historic barony of Omagh West and the civil parish of Urney. The town has a ruined castle and two ancient tombs known as the Druid's Altar and Todd's Den. It had a population of 2,980 people at the 2021 census. The town hosts some of the district's key events each year, including the Derg Vintage Rally, Dergfest music festival, Red River Festival and the traditional Apple Fair. Castlederg was a traveller's stop along the ancient pilgrimage route to Station Island on Lough Derg. The town boasts ancient ruins and monastic settlements.