Waun Mawn Standing Stone

Waun Mawn is a megalithic site on the southern slopes of the Preseli Mountains in Pembrokeshire. It sits on peat moorland about 1.6 kilometres southwest of Brynberian, near the 339-metre hilltop of Cnwc yr Hŷdd. The site once held a Neolithic stone circle with an estimated diameter of 110 metres, making it the fifth largest in Britain. Four stones remain today, one upright and three lying flat, while nearby Troed y Rhiw has its own standing stones. A solitary 2.3-metre stone stands to the west of the main group. Archaeologist Mike Parker Pearson led excavations in 2017 and 2018 that suggested the circle was built around 3400–3200 BC. He proposed that some of its stones, including a distinctive pentagonal one, were moved to Stonehenge before 2120 BC. A BBC programme in 2021 explored this theory, linking Waun Mawn to the legend of Merlin carrying stones from Ireland. Later work in 2021 found only 30% of the circle had been completed, casting doubt on the scale of any migration. Visitors find a quiet moorland setting with four remaining stones. The standing stone is the tallest at 2.3 metres, while the others lie close by. Nearby Troed y Rhiw has more standing stones, and the wider Preseli range offers open views across Pembrokeshire. The site is reached by a short walk from Brynberian, passing through open heather and grassland. The Preseli ridge to the north frames the landscape, adding to the sense of isolation.