The castle was modernised in a classical style in the late 18th century, with a new entrance inserted in the south side and sash windows throughout.
Elyza was also responsible for the landscaping of the grounds, sweeping away the remains of the original formal gardens and orchards, and for the construction of the impressive octagonal stable block.
Many of William Burn's more extravagant Gothic designs for the most important rooms were not carried out, although a Gothic-style pipe organ was installed (now removed to Kemnay Church).
External works during this period included the construction of the twin gatehouses (still extant), and a grand domed stair and access corridors with loggias in the courtyard (removed).
The evocative interiors represent all periods of the castle's history, from the Medieval stone vaulted Great Hall to the Regency Dining Room.