Grey Abbey in Greyabbey, Northern Ireland, is a medieval monastery founded in 1193 by Affreca, wife of John de Courcy. It's one of the best examples of Anglo-Norman Cistercian architecture in Ulster. Although dissolved in 1541, the abbey's remains are still standing and open to visitors. The site includes the church, cloister, and surrounding buildings, set in the picturesque parkland of Rosemount House. So, if you're into history and ancient architecture, Grey Abbey is definitely worth checking out!