Summer House Approximately 150 Metres South West of Gillingwood Hall

The summerhouse, located approximately 150 metres south-west of Gillingwood Hall, dates from the early to mid-18th century and was built for the Wharton family. It features coursed rubble and ashlar sandstone with Westmorland and Welsh slate roofs. The structure has a T-shaped plan and is set into a hillside, comprising two storeys with a basement at the front and three bays.

The north-east front has a central bay that projects slightly. The basement is constructed of coursed rubble with banded rustication, while the upper section is made of ashlar. The central aedicule bay is adorned with four unfluted Roman Doric columns that support a full entablature and pediment. On either side of this bay are shell niches with a sill band and a blind opening above. A cornice runs along the top, and the roof is hipped with Westmorland slate.

The rear of the summerhouse features a narrower range made of coursed rubble with quoins. The central bay is open, showcasing an apsidal rear wall, with two shell niches flanking a brick oculus in an open pediment, also topped with a Westmorland slate roof. The summerhouse is positioned at a higher elevation than Old Gillingwood Hall, offering impressive views to the north-east. It is built into the hillside, with a quarry behind it that likely provided the stone used for Old Gillingwood Hall and its associated buildings.