Although built on sandstone, the masonry is of limestone. The castle consists of an Inner Ward, with a strong curtain wall, and a less defended Outer Ward with a dry moat at the Inner Ward entrance.
Inner Ward: At the SW is the mediaeval house, consisting of a hall and 2 later wings. The hall is about 10.5 m by 6.6 m, with a large lateral fireplace on the NE side, with big corbels for the hood. To the NW of the Hall is a Buttery and above that a Solar. There are 3 vaulted spaces beneath the Hall, 2 of which were sealed and unused. There is an external staircase and an internal winding staircase leading to the Solar The Solar has a window of Norman style. The walls are of exceptional thickness, and the building might be regarded as a small Keep, until the C13 additions decreased its military character.
The Chapel was added c.1260. It is aligned to true E, without regard to adjacent structures. It is almost as large as the Hall, and much ornamented. It has a high pointed vault. It is of limestone with architectural dressings of sandstone. There are traces of an extensive scheme of painted decoration. Large windows with Early English angle-columns and stiff-leaf capitals. Single sedile, with a lancet window at S of the altar. One window at the S side was later altered to a fireplace, with a large external chimney and a stack resembling 2 circular stacks fused together.
Between the Chapel and Hall is sandwiched a later passage with solars above. From this to the S is a spur, which extends to the Curtain Wall. Outside the latter is a tower: in military terms it gave flanking defence to the curtain, in domestic terms it served for latrines.
To the NE of the Inner Ward is the entrance with gate-towers and 2 large corner towers. The ruinous Old Tower to the NW of the present entrance is probably contemporary with the Hall. The curtain wall and the corner towers are probably c.1230. The most complete feature is the Round Tower, with 4 storeys (the floors restored) and battlements. The windows and door recesses are in deep arch-headed alcoves, as the wall is about 1.5 m thick. The parapet stands on a corbel table and is crenellated.
The curtain walls were heightened several times. The guardroom now serves as the castle ticket office ad shop. It has a shallow first floor vault and an upper storey.
The vaulted gatehouse contains the signs of portcullises and a drawbridge, but some details are due to modern attempts at reconstruction. Recess for the raised drawbridge about 0.9 m deep with housings for the trunnions. Upper rooms with window seats. At the top there is a lookout tower.
The barn at the SE of the Inner Ward is post-0mediaeval. Attached to it is a large hexagonal chimney of unknown purpose, but seemingly domestic, with ovens. At the NE end is the house built c.1880 by J R Cobb, but there are vaulted cellars beneath it which are perhaps mediaeval.
In the Outer War is a large barn, seemingly later in date than the Civil War earthworks at the entrance to the Inner Ward. This barn is about 10 m by about 42 m long, with slightly battered walls and the typical large opposed doorways of a threshing floor, one 4.5 m wide and the other 3 m wide. Nothing survives of its roof structure and it was already roofless by the time of Buck’s engraving in 1740.
There are fragmentary defences of the Outer Ward, including a tower or bastion at the N corner.