Mynydd Maendy (translation: Maindy Mountain) is a hilltop and moorland, near Gilfach Goch, in the County Borough of Rhondda Cynon Taf in south Wales, to the southwest of Tonyrefail. As with the Maindee district of Newport, the name derives from the Welsh maen dy meaning "stone house".
Mynydd Maendy is located about one mile west of the small, former coal mining village of Gilfach Goch in the County Borough of Rhondda Cynon Taf, near the larger community of Tonyrefail. The summit is smoothly rounded and provides rough grazing for sheep. Some parts of the flanks of the hill are forested and it forms part of the Rhondda Forest Area.
A wind farm and an Iron Age Celtic hillfort are located on the summit. On a clear day the large turbines of the wind farm can be seen from over 20 miles (32 km) away, and have raised environmental concerns. The wind farm administrative centre is located in nearby Tonyrefail. The wind turbines have been generating renewable energy since 1993 and was one of the first wind farms in the country. Modern turbines are more efficient, and there are proposals for the twenty existing turbines to be removed and replaced by seven larger structures. These more efficient turbines will have the potential to double the amount of energy generated on the site.
The hillfort is a fortified hill top settlement and features on the Register of Landscapes of Special Historic Interest in Wales. It has been described as "the largest undefended Iron Age/Romano-British (800BC-AD410) settlement in southeast Wales", and would have been a place to which the tribe could retreat in times of danger.
- Owen, Hywel Wyn; Morgan, Richard (2007). Dictionary of the Place-Names of Wales. Gomer. p. 309. ISBN 978-1-84323-901-7.
- "Sheet 154: Cardiff". One inch map of Great Britain. Ordnance Survey.
- Simmons, Ian Gordon (1 November 2003). The Moorlands of England and Wales: An Environmental History 8000 Bc to Ad 2000. Edinburgh University Press. pp. 391–. ISBN 978-0-7486-1731-9. Retrieved 27 November 2012.
- Simmons, Ian Gordon (1 November 2003). The Moorlands of England and Wales: An Environmental History 8000 Bc to Ad 2000. Edinburgh University Press. p. 317. ISBN 978-0-7486-1731-9. Retrieved 28 November 2012.
- "Taff Ely Wind Farm: A repowering report". RWE Innogy. Retrieved 2 May 2016.
- "Mynydd Maendy". The Megalithic Portal. Retrieved 2 May 2016.
- "Mynydd Maendy hillfort". Ancient monuments. Retrieved 2 May 2016.
- "Historic Landscape Characterisation The Rhondda: The Rhondda Historical Processes themes and background". Glamorgan-Gwent Archaeological Trust. Retrieved 2 May 2016.