the castle's private chapel, dedicated to st nicholas, is of a much earlier date and is listed at grade i. the original timber-framed building dates from the late 15th century; it was rebuilt in brick in 1717 by john vanbrugh and extended during the 19th century. john betjeman suggests that the attribution to vanbrugh is incorrect since thomas fetherston contracted for the work in 1716. the transepts were added in 1829. the chancel roof is medieval and the furniture of the chancel is of about 1552. the north and south gates to the chapel date from 1722 and were formerly fences to the old hall; they are listed at grade ii.