Merthyr Tydfil (/ˈmɜrθər ˈtɪdvɪl/; Welsh: Merthyr Tudful [ˈmɛrθər ˈtɨːdvɨ̞l]) is a town in Wales, with a population of about 30,000. Although once the largest town in Wales, it is now ranked as the 15th largest urban area in Wales. It also gives its name to a county borough, which has a population of around 55,000. It is located in the historic county of Glamorgan. It is often referred to simply as 'Merthyr'. The current administrative area of the Merthyr County Borough consists of the northern part of the Taff Valley and the smaller neighbouring Taff Bargoed Valley.

According to legend, the town is named after Saint Tydfil, a daughter of King Brychan of Brycheiniog. According to her legend she was slain at Merthyr by pagans around 480; the place was subsequently named Merthyr Tydfil in her honour. Although the usual meaning of the word merthyr (from the Latin martyrium) in modern Welsh is 'martyr', it is probable that the meaning here is "church (in memory of a saint or on his/her grave)." Similar examples, all from south Wales, include Merthyr Cynog, Merthyr Dyfan and Merthyr Mawr. The Cornish and Breton language equivalents, in place names, are merther and merzher.

Maxwell Boyce MBE (born 27 September 1945) is a Welsh comedian, singer and former coal miner. He rose to fame during the mid-1970s with an act that combined musical comedy with his passion for rugby union and his origins in the mining communities of South Wales. Having sold more than two million albums in a career spanning four decades, and playing to full houses all around the world, Boyce is one of the most successful and enduring entertainers in Welsh history.

Max Boyce was born in Glynneath. He has always lived there, but his family were originally from Ynyshir in the Rhondda Valley. A month preceding Boyce's birth, his father died in an explosion in the coal pit where he was working. At the age of fifteen, Boyce left school, went to live with his grandfather, and followed his father's footsteps by working in a colliery "for nearly eight years". In his early twenties, he managed to find work in a factory instead, but his earlier mining experiences were to influence his music considerably in later years.