Basingwerk Abbey (Welsh: Abaty Dinas Basing) is the ruin of an abbey near Holywell, Flintshire, Wales, in the care of Cadw (Welsh Heritage).
The abbey was founded in 1132 by Ranulph de Gernon, 2nd Earl of Chester, who brought Benedictine monks from Savigny Abbey in southern Normandy. In 1147, the abbey became part of the Cistercian Order and therefore a daughter house of Buildwas Abbey in Shropshire. In 1157, the abbey was given the manor of Glossop by King Henry II. The hilltop Monks’ Road and the Abbot’s Chair in Glossop is a reminder of the monks’ efforts to administer their possession. Earlier on, they had received the manor of West Kirby from the Earls of Chester. In the 13th century, the abbey was under the patronage of Llywelyn the Great, Prince of Gwynedd, and his son Dafydd ap Llywelyn gave St Winefride’s Well to the abbey. The monks harnessed the power of the Holywell stream to run a corn mill and to treat the wool from their sheep. In 1536, abbey life came to an end with the Dissolution of the Monasteries. Its dissolution was made lawful by the Dissolution of the Lesser Monasteries Act.
Two centuries earlier a Welsh seer, Robin Ddu ("Robin the Dark" said the roof on the refectory would do very nicely on a little church under Moel Famau. It did. When the abbey was sold, the roof went to Cilcain church and the amazing Jesse window went to the church at Llanrhaeadr-yng-Nghinmeirch.
Today, the abbey ruin is part of Greenfield Valley Heritage Park.