Abertillery (Abertyleri) is a town in the county borough of Blaenau Gwent in southern Wales, north-west of Newport, originally on the Great Western Railway. Its population rose steeply during the period of mining development in South Wales, being 10,846 in the 1891 census and 21,945 ten years later. Lying in the mountainous mining district of the former counties of Monmouthshire and Glamorganshire, in the valley of the Ebbw Fach, the population was traditionally employed in the numerous coalmines, ironworks and tinplate works, now defunct. Further up the same valley are the mining townships of Nantyglo and Blaina.
Abertillery has a traditional-style town centre and several small schools. Today, its population numbers just over 11,000 and it thought to be declining. Noted for its unspoilt rural scenery, Abertillery neighbours the small districts of Aberbeeg, Cwmtillery and Six Bells.
Over the past couple of decades the town has been transformed from industrial relic into the clean, modernised area it is today - this has largely been achieved due to large amounts of European Union Objective One funding which has helped the town remove unsightly reminders of the industrial past. Many of these areas have been utilised as playing fields, business parks or mixed use land (including the local comprehensive school)
A recent windfarm proposal for the mountainside above the community of Cwmtillery has been revived despite opposition to the initial proposal drawing large support. This included a group tagged SCAM (Save Coity and Mynydd James), which led to the application being removed with Blaenau Gwent County Council before being re-submitted on a much smaller scale. The SCAM group is still active in the opposition to the proposal and holds regular meetings in the local area concerning the subject.
The town's name is pronounced with the emphasis on the penultimate syllable, i.e. it rhymes with Mary, as in a song made popular by Welsh entertainer Ryan Davies: "Blodwen and Mary from Abertillery..."