While the present monument was built during the 12th century, it sits upon the site of an earlier, 6th century monastery built by St David, the patron saint of Wales.
Er mai yn y 12fed ganrif y codwyd yr eglwys bresennol, mae'n sefyll ar safle mynachdy cynharach o'r 6ed ganrif a godwyd gan Dewi Sant, nawddsant Cymru.