This Unesco-listed site is a complex of three churches in one, dating from the 11th century and built over 400 years. Now under one huge pitched wooden roof, they represent some of the region's most wonderfully preserved churches. The monastery also houses an icon-filled Byzantine Museum. Get there by following the narrow, winding main street to the opposite side of the valley. Opening hours can fluctuate; you can generally find the priest (plus key) at the nearby coffee shop.