241 Cornish Archaeology 55, 2016, 241–248 A Mesolithic pit at Penans Farm, Grampound, Cornwall ANDY M JONES with a contribution from DANA CHALLINOR In 2016 an archaeological watching brief was undertaken by Cornwall Archaeological Unit at Penans Farm, Grampound. The feldwork led to the discovery of a pit which was notable because it contained charcoal and pieces of quartz. In the absence of artefacts, it was anticipated that the pit would probably prove to be of Neolithic or Bronze Age date. However, the resulting radiocarbon determination, 6563–6428 cal BC, fell in the later Mesolithic period. Securely dated Mesolithic sites are extremely rare in Cornwall, and this paper considers the wider context of the pit and its signifcance. In July 2016 Cornwall Archaeological Unit was commissioned by Qila Energy to undertake an archaeological watching brief at Penans near Grampound, in advance of construction of an anaerobic digester / gas injection plant. A single signifcant archaeological feature was uncovered, which is reported on here. Location and background The phase 1 project area, which covered 0.4 hectares (Fig 1) (centred at SW 95263 49210), is located in the parish of Grampound with Creed. Prior to the development the area was a ploughed feld, and there were no known archaeological features within it. The pit was situated approximately 64m above OD. The site is part of a long-settled area, being ringed by settlements of both medieval and later prehistoric date. Penans Farm, frst documented in 1326, lies approximately 200m to the south, the settlement of Trewinnow Meor, frst recorded in 1337 is approximately 500m to the north east, and Tybesta, frst recorded in 1086, lies 500m to the south west (Cornwall Historic Environment Record reference numbers MCO16036; MCO18058; MCO11670). In addition, 500–700m to the west, the National Mapping Programme has identifed enclosed settlements and feld systems of later prehistoric or Romano-British date (MCO8881; MCO21626; MCO30043), which are visible as cropmarks on aerial photographs. Penans Farm (formerly Pennans) includes a large early eighteenth-century house, and the project area falls within the former ornamental landscape associated with it; the feld boundary south of the development area marks the line of an avenue leading to the house (MCO40755; Pett 1998, 141–2, fg 54). Results from the watching brief A geophysical survey was carried out by TigerGeo in advance of the archaeological watching brief (Roseveare 2016). The survey revealed indications of at least one ploughed-out feld boundary, as well as a number of parallel, slightly curving features aligned roughly north–south, which were interpreted as likely to be evidence for medieval ridge and furrow.