Cefn Onn railway station was a halt on the Rhymney Line

Rhymney Line

The Rhymney Line is a commuter rail line running from Central Cardiff through the Rhymney valley via Heath and Llanishen in the north of the city, to Caerphilly, Bargoed and Rhymney.-History:...

 between Cardiff

Cardiff

Cardiff is the capital, largest city and most populous county of Wales and the 10th largest city in the United Kingdom. The city is Wales' chief commercial centre, the base for most national cultural and sporting institutions, the Welsh national media, and the seat of the National Assembly for...

 and Rhymney

Rhymney

Rhymney is a town and a community located in the county borough of Caerphilly in south-east Wales, within the historic boundaries of Monmouthshire. Along with the villages of Pontlottyn, Fochriw, Abertysswg, Deri and New Tredegar, Rhymney is designated as the 'Upper Rhymney Valley' by the local...

, Wales

Wales

Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...

 opened in 1871. It was replaced by Lisvane & Thornhill, a short distance to the south, and closed on 27 September 1986.

Today

Both of the platforms remain, but undergrowth have consumed most of it. The Up shaped tower remains along with the mile post indicating 6 miles to Cardiff. The bridge connecting the two platforms was removed in 1999. One can still access the right platform via the former Great Western fencing.