Orford Castle lies at the western edge of the village of Orford in Suffolk. It is the earliest castle in England for which documentary evidence of its building survives. The Pipe Rolls record its construction by King Henry II between 1165 and 1173 to a total cost of #1414 9s 2d. It was a symbol of the King's power, strategically placed both to uphold royal authority in a region thickly planted with castles of powerful lords and to guard the coast against invasion. The castle has a number of special claims of interest which include the unique design of the polygonal keep and the fact that it was one of the earliest castles in the country to use mural or flanking towers along the curtain wall.
In essence a single circular ditch with counterscarp bank defined the extent of the castle complex, within which the keep was centrally placed. The curtain wall would have defined a roughly circular bailey with the keep situated in the northern half. A section of curtain wall and the outline of one mural tower are revealed in earthwork form as a robber trench some 7m to the north of the keep. The remaining stretch of wall and towers lay within the ditches which surround the keep on its south, east and west sides. This is not part of the castles defences as so often has been suggested, but in fact represents quarrying, initially created during the removal of the curtain wall and towers and then deepened by the removal of sand.
The keep is the only standing structure to survive. It remains in good condition standing some 30 metres high and was constructed from at least 4 different kinds of stone including local septaria-a sandy coloured mudstone, oolithic limestone, coralline crag, and, Caen stone.
At the top of the south eastern turret of the keep a reinforced concrete roof was constructed during the Second World War. This was originally intended to hold an anti-aircraft gun but instead housed a radar observation post.