Nos. 5, 5a and 5b Castle Hill Road

Nos. 5, 5a, and 5b Castle Hill Road were built around 1868 as an annex to Castle Hill House by Wollaston Knocker, who was the owner of Castle Hill House and served as town clerk.

The building is constructed of yellow brick with red brick voussoirs and features a slate roof that is concealed under a parapet on the north-east side. It is two storeys high and consists of four bays with a side entrance.

The north-east entrance front of no. 5 includes a parapet and a plain band between the floors. The sash windows have horns and only vertical glazing bars. At the southern end, there is a two-storey, one-bay 18th-century section that features a first-floor six-over-six sash window with red brick voussoirs, along with a ground-floor entrance that has a bracket cornice, reeded pilasters, and panelled reveals. The south-west side of the building has sash windows with verticals only on the first and second floors.

Inside no. 5, there is a straight flight staircase with moulded balusters and a turned newel post. One window on the first floor rear elevation retains wooden shutters similar to those found at no. 7. The basement contains a barrel-vaulted strong room measuring approximately 15 by 12 feet, which has a six-inch thick locking iron door. At the far end of this strong room, there is a blocked tunnel that leads to the air raid shelter room of Castle Hill House.