Between June and July 2023 ADAS carried out an archaeological watching brief for Jessop & Cook Architects on behalf of Hertford College of groundworks required for repairs to the Trill Mill Stream retaining wall at Warnock House, rear of 41-43 St Aldate's, Oxford, OX1 1DQ. The objective of the watching brief was to record all archaeological remains exposed during groundworks. Prior to the works taking place, a Level 2 historic building recording survey was undertaken to record the wall. The archaeological monitoring recorded the presence of a brick-lined drain, a brick garden wall and a stone wall. A post medieval occupational deposit and evidence for more recent construction possibly relating to Warnock House and the Trill Mill Stream retaining wall were also identified. A large assemblage of finds, comprised of ceramic fragments, glass, animal bones and horn cores, clay pipe and a medieval billhook, was also retrieved from the archaeological monitoring. The finds provide useful information on the types of activities carried out at the Site, specifically butchery, tanning and horn working activities during the post medieval period, which aligns well with archaeological and historical evidence for tanneries within the vicinity of the Site during this period. Artefacts from earlier periods including fragments of earthenware and whiteware pottery from the medieval and early post-medieval periods and the stems and a bowl from mid-17th century clay pipes were also found. Together, these suggest a deposition of material at the Site from as early as the medieval period. The finds also indicate a date of construction for the stone wall, brick drain and garden wall during the 18th to 20th century. The Trill Mill Stream retaining wall was observed to truncate the brick Garden Wall which suggests a much later date for the construction of the retaining wall than previously thought.
Sophie Honey (Sun,) studied this question.