Castell-Du, Sennybridge

Cadw's description

Summary description and reason for designation

The following provides a general description of the Scheduled Ancient Monument.

Castell Du, also known as Rhyd y Briw, consists of the remains of a castle, dating to the medieval period. The castle is located on the SW side of Sennybridge and commands the crossing of the river Senny at its junction with the Usk. The remains consist of a stone wall 26m in length, orientated ENE/WSW, with a D-shaped tower projecting from the centre. The tower is 6m in diameter and stands to a maximum height of 6m. Much of the original facing stone has been lost, exposing the rubble interior, although a section survives on the W side. Below the tower on the E side is a large chunk of fallen masonry lying on its side, surrounded by fallen stones. To the W of the tower is a stretch of turf-covered walling, probably the remains of a range. Most of this walling is hidden below the vegetation, but one section stands to 2m high adjacent to which is a narrow stone-built passage that leads into the extant WWII pillbox. This pillbox is one of two built on the castle site using masonry to mimic the castle walling. The second, on the E side, now lies within a neighbouring garden. Little is known of the history of the castle, although it is thought to have been constructed by Llywelyn ab Gruffudd around 1262. Records suggest that it was possibly the 'new castle beyond Brecon' destroyed by the then Lord Edward (later Edward I) in 1265. The surviving structural elements on the site may belong to a subsequent castle, as records show the use of the Rhy y Briw into the 1270s.

The monument is of national importance for its potential to enhance our knowledge of medieval defensive practices. The monument is well-preserved and an important relic of the medieval landscape. It retains significant archaeological potential, with a strong probability of the presence of both structural evidence and intact associated deposits.

The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive.