Crumlin is a town, community and electoral ward in Caerphilly county borough in South Wales. It is situated in the Ebbw River valley, 5 mil…Crumlin is a town, community and electoral ward in Caerphilly county borough in South Wales. It is situated in the Ebbw River valley, 5 miles west of Pontypool, within the historic boundaries of Monmouthshire.