St Briavel's Castle survives well with its moat, curtain wall, gatehouse and royal apartments in good condition. The upstanding remains are a good example of an enclosure castle of the 13th century. Sub-surface deposits within the castle and moat will contain archaeological information and environmental evidence relating to the castle and the wider landscape. Notice boards explain concisely the history and functions of the various parts of the castle, and it can be visited by the public in its present function as a Youth Hostel, providing a valuable educational resource. The enclosure castle of St Briavels is recorded in the early 12th century, but is thought to have its beginnings in the 11th century as a motte and bailey castle. This long history of use and adaptation will provide evidence of changing approaches to defensive problems and castle building over time. It was one of a sequence of castles along the border, built as part of a defensive strategy against the Welsh. In the 13th century it was strengthened in a huge castle building programme undertaken for the conquest of Wales and the Welsh wars of 1277, 1282-3 and 1294-5. The gatehouse can be seen as part of the sequential development of castle gatehouses formed by projecting mural towers on either side of an entrance passageway which culminated in the grand castles of Harlech, Beaumaris, Caerphilly and Tonbridge. St Briavel's Castle was frequently visited by the kings of England including King John, Henry II and Edward II, and had royal apartments especially constructed to accomodate them. These royal associations will give an insight into social organisation in the medieval period, and because of the consequential high profile, may provide additional historical documentary evidence which reflects the status of the castle. Apart from its military function the castle was the judicial centre for the Forest of Dean and an arsenal for locally produced weaponry.
The monument includes an enclosure castle situated on the edge of a steep scarp above the River Wye, where the land falls away sharply to the river to the west. The castle appears to have been sited to control the nearby ford at Bigsweir. The irregular plan of the castle has led to the suggestion that it lies on the site of an earlier earthwork, and that in its earliest form it may have been an earthen motte with a timber or stone bailey, dating to the early part of the 12th century. Although the precise date of its foundation is not known, it appears not to have been in existence when William Fitz Baderon acquired the estate in about 1086, and it is likely that he built the first castle on the site at this time as part of a defensive scheme started by William Fitz Osbern against the Welsh. The first known record of the site dates from 1131. By the later 12th century a square stone keep, which was said to have been over 100ft high, had been constructed on top of the castle motte, and in the 13th century a curtain wall was added enclosing an area of 0.61ha. Between 1209 and 1211 extensive additions appear to have been undertaken to the fabric of the castle, including the construction of a two-storey domestic range on the north west side which is thought to have been the 'royal apartments' mentioned in documents of 1227, and which replaced in importance and function the earlier hall which lay on the north side of the ward of the castle. Also at this time the twin towered gatehouse with a defended passage was added. The structure was originally conceived as a keep gatehouse, that is a gatehouse which could be closed and defended against attack from the rear as well as the front. The gatehouse was rebuilt by Edward I in 1292-93 to improve the defences of the castle against Welsh attack and to provide a more prestigeous residence for the Royal Constable. The entrance passage was closed by three barriers each consisting of a portcullis backed by a pair of massive doors. Smaller doors, each protected by its own portcullis, originally led into the side rooms and upper floors of the gatehouse. In the 14th century a chapel was built in the castle ward, replacing an earlier timber chapel. The upstanding remains of the castle, which have survived into the 20th century, date mainly from the early 13th century and comprise a dry moat with a pond in its north east side, rubble curtain walls, fragments of the square keep on the motte, the two-storey domestic range, the site of the hall with its fireplace and the twin towered gatehouse with its defended passage, above which are a group of rooms. The 14th century chapel stands on the west side of the bailey against a building which houses a reused 14th century fireplace. Adjacent to the west side of the castle moat is a level piece of land, the only available flat ground before the land falls away sharply to the west. It has been suggested that this piece of land, called the 'Tump', was part of the early castle but there is no direct evidence for this, and it appears to be outside the limits of the moat. This area is not, therefore, included in the scheduling. It is possible that the outer edge of the moat on the north and east side may extend under the road and the George public house, but it is considered that disruption of the archaeological levels in subsequent road construction and by the cellars of the George, have removed archaeological deposits in these areas, and they are also not included in the scheduling. The castle was the Crown's administration centre for the Forest of Dean, and there were many royal visitors to the castle throughout the early Middle Ages. These royal visitors included King John, who visited on five separate occasions, Henry II who made four visits between 1220 and 1230, and Edward II who stayed there in 1321. The castle also fulfilled a number of administrative functions and was the seat of legal administration for the area; the Hundred Court, the Court Baron of the manor and castle, the Court of Criminal jurisdiction and the Mine-Law Court were all held there. All offenders from the 96 bailiwicks of the Forest were brought to the castle to be imprisioned. The castle remained in use as a courthouse and prison long after it had lost its military function. It also served as an arsenal for locally produced weaponry. With the conquest of Wales completed in the late 15th century, the importance of the castle rapidly declined. In 1680 the unused parts of the castle were demolished. The keep collapsed in 1752, by which time the great hall had also been demolished, leaving only the former royal apartments and the gatehouse still in use. In 1777 the east tower collapsed and destroyed the adjoining buildings. The castle was used as a debtors' prison until 1842, and the gaolers are said to have run an ale house there from 1702. The castle, having been allowed to decay, began to be restored in the late 19th century, and was rendered habitable in 1906. In 1952 it was occupied by the Youth Hostels Association, and is now a Youth Hostel. The castle is a Listed Building Grade I and is in the care of the Secretary of State. (Scheduling Report)
Remains of castle, and curtain wall, now a Youth Hostel. Early C13 and c1292-93, later modifications especially in C19 and C20. Principally in coursed sandstone, with stone slate roofs. What remains is the 3-storey gatehouse of late C13 with two D-shaped towers flanking a crenellated main entrance over the moat, now dry, with the original C13 hall range immediately behind, to the right, and with a restructured C19 facade, then cross wing including the chapel of late C13; this all lies in the north-west corner of a roughly oval curtain wall which is broken in various places, all set to a mound with former moat. The gate house is in 3 storeys and basement with glacis to base of towers; left has five 2-light C19 or later casements in wood with transom, right one similar, 1 deep arrow slit, and 3 small single lights, central great doors in segmental pointed arch in 3 orders, return face right has 4 arrow slits and three 2-light wood casements, one with transom; then 2 storey block with crenellated top, with C19 windows, two 3-light with transom and one 2-light the same over one 3-light and two 2-light casements without transom, continued to gable with fine decorative octagonal chimneystack with trefoil heads and crocketted gables and a small spire over 2-light casement with transom and a lofty C19 door. Interior: west tower includes fine heavily detailed carpenter's staircase at first floor, and hooded C13 fireplace, oak plank floors and deep embrasured openings, the current dining room includes fireplace with moulded overmantel under a blocked arch and one minute light in a deep embrasure. Large hooded C13 or C14 fireplace at first floor in north west tower. The Chapel, now a games room, is of late C13, has heavy 3-bay roof, double chamfer door, and an original piscina, and includes a 3-light stone casement with heavy transom but tracery now missing from pointed head, and a similar window to room known as King John's bedroom; King John's bedroom includes a very heavy overmantel on triple shafts with carved caps which do not fit the shafting. A very impressive remnant and sited very prominently opposite the Church of St Mary. (Listed Building Report)