The Castle, Stable Court And Covered Riding School Including West Wall Of Riding School

Alnwick Castle is a major medieval fortress substantially developed and altered in the 18th and 19th centuries. The Castle, Stable Court, and Covered Riding School, including the west wall of the Riding School, are listed as a group.

The castle occupies the site of the original Norman motte and bailey plan. By 1138, a stone-built border castle with a shell keep had been constructed in place of the motte, forming the nucleus of the present castle with two baileys enclosing about 7 acres. The curtain walls and square towers rest on early foundations, while the inner gatehouse features round-headed arches with heavy chevron decoration.

Following its purchase by Henry de Percy in 1309, the castle was greatly fortified. Work from the early to mid-14th century includes the Barbican and Gatehouse, the semi-circular towers of the shell keep, the octagonal towers of the inner gateway, and the strong towers of the curtain wall. By the 18th century the castle had fallen into disrepair. The 1st Duke employed James Prince and Robert Adam for rehabilitation and extension, Adam being primarily responsible for interior decoration, of which little remains save fireplaces in the Housekeeper's and Steward's Rooms and within the present Estates Office range. Capability Brown landscaped the grounds and filled in the former moat formed by Bow Burn.

The 4th Duke employed Anthony Salvin from 1854 to 1865 at a cost of £1/4 million. Salvin removed Adam's Gothic fancies from the exterior, restored a serious Gothic character, and redesigned the state rooms in imposing grand Italian manner.

The castle is approached from Bailliff Gate through the crenellated Barbican and Gatehouse of the early 14th century, featuring a lion rampant (replica) over the archway, projecting square side towers with corbelled upper parts, and a fortified passage over the dry moat to a vaulted gateway flanked by polygonal towers. Stone figures on the crenellations here, on Aveners Tower, on Record Tower, and on the Inner Gateway were carved around 1750–70 by Johnson of Stamfordham and probably reflect an earlier similar arrangement.

In the Outer Bailey to the north stand the West Garrett (partly Norman), the Abbott's Tower (circa 1350) with a rib-vaulted basement, and the Falconer's Tower (1856). To the south are the Aveners Tower (18th century), the Clock Tower opening into the Stable Yard, an 18th-century office block, the Auditor's Tower (early 14th century), and the Middle Gateway (circa 1309–15) leading to the Middle Bailey. The most prominent feature on the castle's west side is the large Prudhoe Tower by Salvin and the polygonal apse of the chapel adjacent to it.

In the Middle Bailey, to the south are the Warders Tower (1856) with a lion gateway leading by bridge to grand stairs into the walled garden, the East Garrett, and the Record Tower (14th century, rebuilt 1885). The curtain wall to the north contains two blocked windows probably from an early 17th-century building now destroyed, and the 'Bloody Gap', a piece of later walling possibly replacing a lost tower. Adjacent is a small 14th-century watch tower called Hotspur's Seat, followed by the Constable's Tower (early 14th century, unaltered) with a gabled staircase turret, and the Postern Tower (early 14th century, also unaltered). North-west of the Postern Tower is a large terrace made in the 18th century and rebuilt in 1864–65, displaying old cannon.

The Keep is entered from the Octagon Towers (circa 1350) which bear 13 heraldic shields below the parapet and anthropic figures, with a vaulted passage expanded from the Norman gateway; fragments of chevron on the former outer arch remain visible inside. The present arrangement of the inner ward is largely Salvin's work, featuring a covered entrance with a projecting storey and lamp-bracket at the rear of the Prudhoe Tower and a corbelled corridor at first-floor level on the east. A medieval draw well stands on the east wall next to the original keep doorway, now a recess. The keep and curtain walls are largely medieval except for 18th-century interior work on the west side and the Prudhoe Tower and Chapel.

The interior contrasts sharply with the rugged medieval exterior, displaying sumptuous Renaissance decoration largely executed by Italian craftsmen—Montiroli, Nucci, Strazza, and Mantavani—inspired by Italian sources. The chapel, with its family gallery at the east end, contains four short rib-vaulted bays and a shallow three-light apse; side walls have mosaics now covered with tapestry. The grand staircase with its groin-vaulted ceiling leads to the Guard Chamber, from which an ante-room opens west into the Library (in the Prudhoe Tower) and east into the Music Room, which features a fireplace with Dacian captives by Nucci. Beyond these lie the Red Drawing Room with a caryatid fireplace by Nucci, and the Dining Room, whose ceiling design is copied from San Lorenzo in Rome and which contains a fireplace with a bacchante by Strazza and a faun by Nucci.

South of the Middle Gateway are Salvin's impressive Kitchen quarters, where the oven was designed to burn a ton of coal per day. West of the Stable Courtyard, with a 19th-century Guest Hall at the south end, stands the 19th-century covered riding school with stable to its north, its west wall forming the east side of Narrowgate. The corner with Bailliff Gate features an obtuse-angled tower of two storeys with a depressed ogee-headed doorway from the street and merlons.