The Percy family built the Keep in the late 14th century. This was one of the finest
in the country, with an advanced design that would have provided impressive
accommodation as well as a status symbol worthy of such a powerful family. The
cross-shaped keep is like a castle within the castle. It is built on three main
storeys and includes a great hall, chapel, kitchens, storerooms and various chambers.
A central "lightwell" provides daylight to some of the inner rooms and also allows the
capture of rainwater into a tank which has a separate channel to allow water to be
diverted to flush the latrines. A tall lookout tower completes the design.
Two chambers on the second floor (the Duke's rooms) were restored by the 4th Duke in
the 1850s. These were used for entertaining when the Duke visited from Alnwick and
remained in use until 1987.