A wind farm opposed by Swansea Valley campaigners is being built on an “ancient version of the M4”, a deputy mayor has said.
Work started on the 15-turbine Mynydd y Betws wind-farm late last year.
Campaigners opposed the build because of what they claimed would be an unacceptable traffic increase in transporting the turbines up the Swansea Valley.
But this week archeologists said they had uncovered a 5,000-year-old neolithic “stone row”, which could raise questions over the future of the project.
After the find, Pontardawe deputy mayor Huw Evans highlighted the importance of preserving the area’s ancient heritage.
“Mynydd y Betws, the Baran and Mynydd Gellionnen are all littered with ancient monuments, stone circles and traces of pre-Christian worship,” he said.
“Gellionnen Chapel itself is located where three lay-lines cross and is believed to be a site of pre-Christian meeting or worship. Our area appears to have been an ancient M4 of its day as both a route for trading and also of congregation.”
The find was pointed out to archaeologists from the Dyfed Archeological Trust, as well as experienced freelancers Sandy and Helen Gerrard, who are convinced the discovery is genuine. Cambrian Renewable Energy Limited, the company building the turbines, said its own archaeologists had met at the site yesterday and were preparing a statement next week.
A spokesman from Cambrian Renewable Energy Limited said: “Cambrian Renewable Energy Limited is consulting with its own archaeologists and Carmarthenshire Council on the potential significance of some findings.
“Further statements will be issued when more information becomes available.”
Gwenda Thomas AM has also written to the minister responsible for heritage, Huw Lewis AM, concerning the find.