 | Drefach lies at the confluence of three fast flowing streams, the Nant Bargoed, Nant Esgair and Nant Bran. In the 19th and early 20th century, it was the centre of a thriving woollen industry, earning the nickname ‘the Huddersfield of Wales’. |
| Drefach Felindre has little industry today. The mills still stand as monuments to the past but have been put to other uses. The museum of the Welsh Woollen industry, now the National Wool Museum, was opened in 1976 and is located in the historic former Cambrian Mills. |  |
 | Pen-rhiw chapel originally stood in Drefach, but was re-erected at the Welsh Folk Museum, St Fagans in 1956. It is still a consecrated building with worship taking place at regular intervals. Pen-rhiw chapel was opened in 1777 and is typical of early Welsh Nonconformist chapels. |
| Griffith Jones was a priest in the Carmarthenshire village of Llanddowror and is remembered for establishing circulating schools in Wales, i.e. tutors going from one church to another teaching the locals to read the Bible. He was born in Pant-yr-efail in the parish of Penboyr. |  |
