Kenilworth Castle is a castle in the town of Kenilworth in Warwickshire, England, managed by English Heritage; much of it is in ruins. The castle was founded after the Norman Conquest of 1066; with development through to the Tudor period. It has been described by the architectural historian Anthony Emery as "the finest surviving example of a semi-royal palace of the later Middle Ages, significant for its scale, form and quality of workmanship".

Kenilworth played an important historical role: it was the subject of the six-month-long siege of Kenilworth in 1266, thought to be the longest siege in medieval English history, and formed a base for Lancastrian operations in the Wars of the Roses. Kenilworth was the scene of the removal of Edward II from the English throne, the perceived French insult to Henry V in 1414 of a gift of tennis balls (said by John Strecche to have prompted the campaign that led to the Battle of Agincourt), and the Earl of Leicester's lavish reception of Elizabeth I in 1575. It has been described as "one of two major castles [with Caerphilly Castle] in Britain which may be classified as water-castles or lake-fortresses...".

The castle was built over several centuries. Founded in the 1120s around a powerful Norman great tower, the castle was significantly enlarged by King John at the beginning of the 13th century. Huge water defences were created by damming the local streams, and the resulting fortifications proved able to withstand assaults by land and water in 1266. John of Gaunt spent lavishly in the late 14th century, turning the medieval castle into a palace fortress designed in the latest perpendicular style. The Earl of Leicester then expanded the castle during his tenure in the 16th century, constructing new Tudor buildings and exploiting the medieval heritage of Kenilworth to produce a fashionable Renaissance palace.

Architecture and landscape

Although now ruined as a result of the slighting, or partial destruction of the castle by Parliamentary forces in 1649 to prevent it being used as a military stronghold after the English Civil War, Kenilworth illustrates five centuries of English military and civil architecture. The castle is built almost entirely from local New Red Sandstone.Emery 2000, p.340.

Entrance and outer bailey wall To the south-east of the main castle lie the Brays, a corruption of the French word braie, meaning an external fortification with palisades.Morris 2010, p.5.An alternative view is that the name "brays" derives instead from a corruption of the word "bays", a medieval word describing a sequence of ponds similar to the lake structure at Kenilworth; see Only earthworks and fragments of masonry remain of what was an extensive 13th-century barbican structure including a stone wall and an external gatehouse guarding the main approach to the castle.Pettifer, p.258. The area now forms part of the car park for the castle.

Beyond the Brays are the ruins of the Gallery Tower, a second gatehouse remodelled in the 15th century. The Gallery Tower originally guarded the long, narrow walled-causeway that still runs from the Brays to the main castle.Thompson 1965, p.158. This causeway was called the Tiltyard, as it was used for tilting, or jousting, in medieval times. The Tiltyard causeway acted both as a dam and as part of the barbican defences. To the east of the Tiltyard is a lower area of marshy ground, originally flooded and called the Lower Pool, and to the west an area once called the Great Mere. The Great Mere has been drained and cultivated as a meadow, but it was originally a large lake covering around , dammed by the Tiltyard causeway.Hull 2009, p.49.

The outer bailey of Kenilworth Castle is usually entered through Mortimer's Tower, today a modest ruin but originally a Norman stone gatehouse, extended in the late 13th and 16th centuries. The outer bailey wall, long and relatively low, was built mainly by King John; it has numerous buttresses but only a few towers, being designed to be defended primarily by the water system of the Great Mere and Lower Pool. The north side of the outer bailey wall was almost entirely destroyed during the slighting. Moving clockwise around the outer bailey from Mortimer's Tower, the defences include a west-facing watergate, which would originally have led onto the Great Mere; the King's gate, a late 17th-century agricultural addition; the Swan Tower, a late 13th-century tower with 16th-century additions, then named after the swans that lived on the Great Mere; the early 13th-century Lunn's Tower; and the 14th-century Water Tower, so named because it overlooked the Lower Pool."Pettifer, p.258; Morris 2010, p.24, 29."

Inner court Kenilworth's inner court consists of a number of buildings set against a bailey wall, originally of Norman origin. It exploits the defensive value of a natural knoll that rises up steeply from the surrounding area.Pettifer, pp.257–8. The 12th-century great tower occupies the knoll itself and forms the north-east corner of the bailey. Ruined during the slighting, the great tower is notable for its huge corner turrets, essentially hugely exaggerated Norman pilaster buttresses.Thompson 1991, p.77; Pettifer, p.258. Its walls are thick, and the towers high.Hull 2009, p.102. Although Kenilworth's great tower is larger, it is similar to that of Brandon Castle near Coventry; both were built by the local Clinton family in the 1120s.Morris 2010, p.37. The tower can be termed a hall keep, as it is longer than it is wide. The lowest floor is filled with earth, possibly taken from the earlier motte that may have been present on the site, and is further protected by a sloping stone plinth around the base. The tall Tudor windows at the top of the tower date from the 1570s.Morris 2010, p.8.

Much of the northern part of the inner bailey was built by John of Gaunt, a son of King Edward III, between 1372 and 1380.Emery 2000, p.402. This part of the castle is considered by historian Anthony Emery to be "the finest surviving example of a semi-royal palace of the later middle ages, significant for its scale, form and quality of workmanship". Gaunt's architectural style emphasised rectangular design, the separation of ground floor service areas from the upper stories and a contrast of austere exteriors with lavish interiors, especially on the 1st floor of the inner bailey buildings.Emery, pp.205–6. The result is considered "an early example of the perpendicular style".Stokstad, p.77.

The most significant of Gaunt's buildings is his great hall. The great hall replaced an earlier sequence of great halls on the same site, and was strongly influenced by Edward III's design at Windsor Castle.Emery, p.205; Thompson 1977, pp.211–8. The hall consists of a "ceremonial sequence of rooms", approached by a particularly grand staircase, now lost."Emery, p.246; Pettifer, p.258." From the great hall, visitors could look out through huge windows to admire the Great Mere or the inner court."Stokstad, p.78; Pettifer, p.258." The undercroft to the hall, used by the service staff, was lit with slits, similar to design at the contemporary Wingfield Manor. The roof was built in 1376 by William Wintringham, producing the widest hall, unsupported by pillars, existing in England at the time.Emery, p.543; Emery 2000, p.401, 404. There is some debate amongst historians as to whether this roof was a hammerbeam design, a collar and truss-brace design, or a combination of the two.An example of the combination of the curved hammerbeam and right-angled collar and truss-brace design can be seen in this depiction of the roof of Westminster Hall.

There was an early attempt at symmetry in the external appearance of the great hall – the Strong and Saintlowe Towers architecturally act as near symmetrical "wings" to the hall itself, while the plinth of the hall is designed to mirror that of the great tower opposite it.Emery 2000, p.340, 403; Morris 2010, p.13. An unusual multi-sided tower, the Oriel, provides a counterpoint to the main doorway of the hall and was intended for private entertainment by Gaunt away from the main festivities on major occasions.Hull 2009, p.118. The Oriel tower is based on Edward III's "La Rose" Tower at Windsor, which had a similar function.Morris 2010, p.17. Gaunt's Strong Tower is so named for being entirely vaulted in stone across all its floors, an unusual and robust design.Morris 2010, p.12. The great hall influenced the design of Bolton and Raby castles. The hall's roof design was independently famous and was copied at Arundel Castle and Westminster Hall.Emery, p.205, 543.

Other parts of the castle built by Gaunt include the southern range of state apartments, Gaunt's Tower and the main kitchen. Although now extensively damaged, these share the same style as the great hall; this would have unified the appearance of Gaunt's palace in a distinct break from the more eclectic medieval tradition of design.Stokstad, pp.77–8. Gaunt's kitchen replaced the original 12th-century kitchens, built alongside the great tower in a similar fashion to the arrangement at Conisbrough.Thompson 1991, p.77. Gaunt's new kitchen was twice the size of that in equivalent castles, measuring .Morris 2010, p.11.

The remainder of the inner court was built by Robert Dudley, 1st Earl of Leicester, in the 1570s. He built a tower now known as Leicester's building on the south edge of the court as a guest wing, extending out beyond the inner bailey wall for extra space.Morris 2010, p.19. Leicester's building was four floors high and built in a fashionable contemporary Tudor style with "brittle, thin walls and grids of windows".Morris 2010, p.19, 48. The building was intended to appear well-proportioned alongside the ancient great tower, one of the reasons for its considerable height.Morris 2010, p.48. Leicester's building set the style for later Elizabethan country house design, especially in the Midlands, with Hardwick Hall being a classic example.Johnson 2000, p.234; Morris 2010, p.48. Modern viewing platforms, installed in 2014, provide views from Elizabeth I's former bedroom.Leicester's Building at Kenilworth Castle reopened after more than 350 years, BBC News. Retrieved 11 November 2014.

Leicester also built a loggia, or open gallery, beside the great keep to lead to the new formal gardens.Stokstad, p.80. The loggia was designed to elegantly frame the view as the observer slowly admired the gardens, and was a new design in the 16th century, only recently imported from Italy.

Base, left-hand and right-hand courts

The rest of Kenilworth Castle's interior is divided into three areas: the base court, stretching between Mortimer's Tower and Leicester's gatehouse; the left-hand court, stretching south-west around the outside of the inner court; and the right-hand court, to the north-west of the inner court.Morris 2010, p.6. The line of trees that cuts across the base court today is a relatively modern mid-19th century addition, and originally this court would have been more open, save for the collegiate chapel that once stood in front of the stables. Destroyed in 1524, only the chapel's foundations remain.Morris 2010, p.29. Each of the courts was designed to be used for different purposes: the base court was considered a relatively public area, with the left and right courts used for more private occasions.Morris 2010, p.24.