A Unesco World Heritage site, the monastery was founded by a hermit, Luke Stiris, who died in 953 and whose tomb became an object of pilgrimage. The Katholikon, a huge archetypal pilgrimage church with marvellous mosaics, is a masterpiece of Byzantine art. The interior decor is mainly 11C, including multicoloured marble facing on the the walls and pillars, jasper and porphyry in the floor, delicate sculptures decorating the iconostasis, and the extraordinary mosaics on the ceilings, pediments and pilasters.