When Ralph Allen built Prior Park mansion in the 1740s he established a formal garden with advice from the poet Alexander Pope and this is shown in the famous Walker engraving of 1750. Together with statuary and walks around the garden a circular ‘Bason’ pool can be seen which at the time lay at the northern extent of Allen’s estate below the house. This was about halfway up the pasture from the existing lakes and Palladian bridge which were constructed in the 1750s when the land and then farm at the foot of the valley was acquired. It is possible that ‘Capability’ Brown was involved in these later developments bringing the English landscape garden style to Prior Park but resulting in the removal of the Bason to create a clear view down the hill.
The excavation by National Trust and Bath and Counties Archaeology Society (BACAS) volunteers during the Festival of Archaeology in July 2023 found remains of the dam wall for the Bason pool; a possible later cascade which then took the spring water that had fed the pool down to the lower lakes; and parts of the buried water culvert network on the hillside.
Further work is planned for next year to discover more of the Bason wall, pool, cascade and culverts of the garden.