Castleknock Castle

Norman castle ruin on school grounds in suburban Dublin

Castleknock Castle is the ruin of a Norman fortification on the grounds of Castleknock College, a Catholic boarding school on the western outskirts of Dublin. The castle dates back to the aftermath of the 12th-century Norman invasion of Ireland. Its Irish name, Caisleán Cnucha, echoes medieval texts that mention the hill as Cnoc or Cnucha. The remains are today embedded within the school grounds and largely inaccessible to the general public.