Abercarn is a town and community in Caerphilly county borough, Wales. It is 10 miles northwest of Newport on the A467 between Cwmcarn an…Abercarn is a town and community in Caerphilly county borough, Wales. It is 10 miles northwest of Newport on the A467 between Cwmcarn and Newbridge, within the historic boundaries of Monmouthshire. An estate at Abercarn was owned by the ironmaster Richard Crawshay; in 1808, it passed to his son-in-law, the industrialist and politician Benjamin Hall.