Plas Baglan Castle was built at the end of the 12th or 13th century on the initiative of the Welsh-Norman family of the Lords of Afan. If it was founded before 1200, its builder could be Morgan ap Caradog, Lord of Afan, who died in 1207. It was a small site belonging to the local lower nobility, but in the fourteenth and fifteenth centuries Plas Baglan was a center of Welsh culture and music. Apparently, the famous poet Dafydd ap Gwilym visited the castle among many bards. The castle fulfilled residential functions in the sixteenth century, but around 1600, due to lack of space for expansion and failure to meet the requirements of an early modern lifestyle, it was abandoned.
The castle was situated on the ridge of the hill, between two streams surrounding it from the north and south, and then joining on the west side. From the more accessible north and east sides the castle was cut off by a 22-meter wide ditch. It had a form similar in plan to a square with a side length of 21-24 meters, surrounded by the perimeter of the walls with a rectangular tower or building in the back of the inner courtyard. It was situated on the longer sides on the north-south line, measured 17.3 x 10 meters and had walls 1.52 meters thick. On the north side there was also a small turret, perhaps acting as a latrine. The entrance gate was placed on the east side opposite the building. It was probably a regular portal pierced in the wall. A smaller building, perhaps an economic one, was located in the north-east corner of the courtyard.
The castle has not survived to modern times. In the forested area, only small fragments of the lower parts of the walls are visible, as well as rubble mounds and relics of former buildings covered with earth. The ditch is currently illegible, probably due to being covered by fallen walls. Entrance to the former castle area is free.
Davis P.R., Castles of the Welsh Princes, Talybont 2011.
Website gatehouse-gazetteer.info, Plas Baglan.