The early castle at Kenilworth consisted of a massive Norman tower, rectangular in shape and three storeys high. Once defended by a wide moat, the shell of this great red sandstone tower, open to the sky, remains an imposing sight. Henry II was certainly impressed by what he saw, and took Kenilworth Castle into royal possession. During three successive reigns, Kenilworth Castle was extensively altered and enlarged. In the 14th century John of Gaunt transformed the castle from a fortress to a grand palace, and built a range of private apartments overlooking the vast lake. The magnificent banqueting hall with a hammer-beam roof was reputed to be almost as important as Westminster Hall at the time.

When Robert Dudley, the Earl of Leicester, took possession of Kenilworth Castle in the 1560s, he instigated further building and modernisation work, and the creation of some formal pleasure gardens. Satisfied with the construction of his impressive new gatehouse at the northern boundary, and his luxurious suite of Tudor apartments (Leicester's Building), Dudley's castle was now 'fit for a Queen'. And that was exactly his intention. His good friend, Queen Elizabeth I, was treated on several occasions to Dudley's stylish hospitality, and none more notable than that in 1575. For nearly three weeks she was entertained with pageants, music, dancing, fireworks, hunting and feasting.

At the death of Robert Dudley, Kenilworth Castle returned to Crown possession. Throughout the Civil War it changed from Royalist to Parliamentarian hands on two occasions, before being partially demolished by Parliamentary troops. By 1650 it was rendered untenable, the huge defensive lake was drained, and the gatehouse was converted to residential accommodation. With the Monarchy restored, Kenilworth Castle passed to the Villiers family until, in 1938, Lord Kenilworth placed his property in the care of English Heritage.

Immortalised, and romanticised, by Sir Walter Scott in his early 19th century novel, Kenilworth Castle is probably one of the finest ruined castles to be seen in Britain today. Dramatically portrayed amidst the gentle rolling countryside of Warwickshire, Kenilworth Castle is a memorable landmark to the powerful Normans, and a fitting memorial to the power games of Elizabethan England. The inner court contains a range of ruinous buildings dating from the 12th to the 16th century, including Leicester's Building. Remaining substantially intact are the great Tudor gatehouse and stabling block from Robert Dudley's time located in the outer court. From a 17th century plan, the Tudor gardens have been reconstructed in the form of a parterre.