The community of Cefn includes the villages of Cefn Mawr, Cefn Bychan, Acrefair, Penybryn, Newbridge, Plas Madoc and Rhosymedre and is situated on the northern slopes of the Dee Valley. As well as the former industrial villages around Acrefair, it also includes some rural areas to the north on the slopes of Ruabon Moors. At the time of the 2001 census, it had a total population of 6,669 in 2,763 households, increasing to 7,051 at the 2011 Census.
The area formerly comprised the townships of Coed Cristionydd and Cristionydd Cynrig (or Cristionydd Kenrick), which became part of the parish of Ruabon. Parts of the townships were formed into the new parish of Rhosymedre in 1844. The corresponding civil parish of Cefn Mawr was formed into the community of Cefn in 1974, under the terms of the 1972 Local Government Act.
- Cefn Community (Parish) Archived 2015-11-19 at the Wayback Machine, Office of National Statistics
- "Community population 2011". Retrieved 18 November 2015.
- Rhosymedre, St John, GENUKI
- Cefn Mawr Parish Council records Archived 2012-05-23 at the Wayback Machine, Archives Wales
- "Ward population 2011". Retrieved 18 November 2015.