Skenfrith Castle (Welsh: Ynysgynwraidd) is a medieval castle located in Monmouthshire, Wales. The castle is in the centre of the village of Skenfrith, located on the banks of the River Monnow, five and a half miles north-west of the town of Monmouth. The first defences were built shortly after the Norman Conquest of 1066, although the remains of the castle that stand today date from the early thirteenth century.