Holy Island (, 'the island of (Saint) Cybi') is an island  on the western side of the larger Isle of Anglesey, North Wales, from which it is separated by a narrow, winding channel. It is called "Holy" because of the high concentration of standing stones, burial chambers and other religious sites on the small island. The alternative and historic name of the island is Holyhead Island. According to the 2011 UK Census, the population is 13,659.