the works may still be traced. Nearer the centre of the county, upon the Ython and the Aran, were other castles. Moelynaidd and Castell Colwyn or Mauds Castle, fortified by the Earl of Chester in 1143, were on the former river, and near them was Cefn-Lys or Castell-glyn-Ython, a rather celebrated Norman castle, but often taken by the Welsh. It was held latterly by the Mortimers, and rebuilt by them in 1142. Dwybod Timpath or Tilloedd, also on the Ython, was a place of great strength of which many fragments of masonry remain. The name has been said to be a corruption of Talbot. This castle was levelled by Llewellyn in 1260. Cwm Aron, on the Aron river, was an early Norman castle, destroyed by the Welsh and restored by Hugh Earl of Chester in 1143. This also came to the Mortimers. There are considerable remains of the earthworks. Near to Presteign were Warden and Stapleton Castles, the latter built by Chandos the founder of Goldcliff Priory. There was also a castle at Clyro, and one upon the Lug at Castell Haled or Vallet; and at Clâs Cwm on the Arrow is some masonry said to represent Brynllys Castle. The remaining parts of South and West Wales containing much open and tolerably fertile land, and having a long and exposed frontier towards the purely Welsh districts of Brecknock, Caermarthen and Cardigan, were the scene of perpetual inbreaks from the Welsh, and required more than usual strength in the defences. The castle of Gloucester, already mentioned, was the base of all extended operations in South Wales. Here the kings of England often held their court, and here their troops were mustered. Brichtric had a castle at Gloucester, but his mound has long been removed, and with it all traces of the Norman building.