Rushen Abbey, near Ballasalla, was founded in 1134 when Olaf I (Óláfr Guðrøðarson), King of Mann and the Isles, granted land to Savignac monks from Furness Abbey; the order merged with the Cistercians in 1147, and the abbey's church, dedicated to St Mary, was completed by 1257. For centuries it was the centre of literacy and record-keeping on the island, and is believed to be where the Chronicle of Mann and other key historical manuscripts were compiled. Dissolved in the 16th-century Reformation, the site fell into neglect before becoming a popular tourist attraction in the early 1900s, then deteriorated again through the mid-20th century. Manx National Heritage acquired the ruins in May 1998 and carried out restoration and archaeological excavation that revealed new details of monastic life. It now operates as a seasonal heritage centre with museum displays, conserved ruins, and family activities exploring medieval Manx history.