Cefneithin (Welsh pronunciation) is a village and community in Carmarthenshire, Wales, in the Carmarthenshire coalfield area. It lies just off the A48 road, 7 miles north west of Ammanford and 9 miles north of Llanelli. Its nearby community villages include Cross Hands, Drefach, Cwmmawr, Foelgastell and Gorslas. The Gwendraeth Fawr river flows nearby and its source is at Llyn Llech Owain, just north of the village. Cefneithin has a chapel (Tabernacl), a village hall (Y Neuadd), a primary school, and a secondary school. The latter, Ysgol Maes y Gwendraeth, was re-opened in 2016 after an extensive renovation and an £18.4m investment; it has 1,000 pupils, of which 157 in sixth form, and resources for children with additional learning needs. Prior to 2016 when the school was called Ysgol Gyfun Maes Yr Yrfa, some of its famous pupils include Nigel Owens (international rugby referee), Jonathan Edwards (MP for Carmarthen East and Dinefwr), TV presenter Alex Jones and British and Irish Lion rugby player, Dwayne Peel.
The local rugby club, Cefneithin RFC, was founded in 1922.
Blaenhirwaun Colliery was situated just outside Cefneithin and was near the extremity of the coalfield. It produced high grade anthracite with an output of about 350 tons per day. 360 people were employed below ground and 80 on the surface. It was served by two vertical shafts sunk to the Green Vein. The No.1 shaft was 10 feet in diameter and 155 yards deep and as the upcast. It was equipped with a Walker Paddle fan which produced about 55,000 cubic feet of air per minute at a water gauge of 3.125 inches. The No. 2 shaft was 13 feet in diameter and 212 yards deep and was the downcast and winding shaft for men and materials.
The former Colliery has been regenerated to become the Mynydd Mawr Woodland Park - a mix of broadleaved woodland and grassland which is home to a diverse collection of wildlife. The area includes footpaths, picnic facilities, information points and a track for mountain bikers and horseriders.
- Craig Bonell, Wales universities rugby & Pontypridd RFC
- Gareth Davies WRU Chairman, played cricket for Cefneithin and Glamorgan 2nds, & rugby for British and Irish Lions
- Jac & Wil Davies, Welsh singing duet
- Robert Dickie (1964 - 2010), professional boxer
- Mark Harries, Wales Under 18s athletics
- Carwyn James, rugby player and coach
- Roy James, Wales Under 19s cricket & Glamorgan 2nd XI
- Alan John, rugby player Llanelli RFC and toured Argentina with Wales in 1968
- Barry John, rugby player
- Clive John, rugby player Llanelli RFC, Wales B
- Gwynoro Jones MP, played rugby for Cefneithin; became Member of Parliament at the age of 27
- William John Jones, rugby player, 1 cap for Wales
- Aneira Thomas, first baby born into NHS at 12:01 am on Monday 5 July 1948
- Huw Thomas, Wales Pool team who beat England and Scotland in the Super League Tournament, Huddersfield in 1979; Welsh Javelin champion at Junior, Intermediate, and Senior Boys categories between 1961 and 1964
- Ian Williams, Wales Youth rugby
- Robert Williams, Wales Under 16s rugby & Swansea RFC
- Ronnie Williams (1939 – 1997), actor and comedian
- "NMR Site Files | Coflein". www.coflein.gov.uk. Retrieved 24 June 2020.
- "Official opening for £18m Ysgol Maes y Gwendraeth". BBC News. 30 November 2016. Retrieved 19 June 2020.
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- "Blaenhirwaun Colliery Explosion - Cross Hands - 1955". Northern Mine Research Society. Retrieved 23 June 2020.
- Woodland Trust. "Mynydd Mawr Woodland Park".
- "BBC Radio Cymru - Jac a Wil". BBC (in Welsh). Retrieved 19 June 2020.
- "JAC A WIL - Sain Records - Music from Wales". sainwales.com. Retrieved 23 June 2020.
- Shipton, Martin; Rinaldi, Chiara (27 February 2018). "Listen to the Martin Shipton meets Gwynoro Jones podcast". walesonline. Retrieved 22 June 2020.
- Thomas, Aneira (16 September 2017). "'I was the first baby delivered by the NHS. It has saved my life eight times'". the Guardian. Retrieved 19 June 2020.
- "'I am the first baby born under the NHS'". BBC News. Retrieved 19 June 2020.