Appendix B: Ring-ditches

Appendix B: Ring-Ditches

Ring-ditches (i.e. ditches presenting more or less circular plans, sometimes interrupted by causeways) appear as crop-marks in many air photographs; they are difficult to interpret and have been referred to in the following Inventory only when they occur near an area of Iron Age or Romano-British settlement. The full range of such crop-marks appears on the accompanying plan, which shows the relationship of all known Prehistoric and Roman monuments in the area of Upper Thames river-gravels, extending from Gloucestershire into Wiltshire. For a summary discussion of the ringditches noted within the area described in the volume (approximately 150), and problems of their interpretation and dating, see I. F. Smith in Archaeology and the Landscape (ed. P.J. Fowler, 1972), chapter vi.

Some ring-ditches are likely to belong to ploughedout Bronze Age round barrows, as shown by the excavation of examples in the area of the Chessels Romano-British settlement at Lower Slaughter (1). Intensive occupation in the gravel terraces (where most of the examples have been noted) seems frequently to have resulted in the obliteration or degradation of pre-existing earthworks; for instance, linear ditches are sometimes seen to cross ring-ditches without interruption, indicating that any former mound or bank was already flattened. The circumstances contrast markedly with those observed in upland situations on chalk or limestone, where earlier monuments were usually left unploughed in Iron Age and Roman times. But there is an occasional indication that certain ring-ditches still enclosed mounds in the Iron Age and Roman periods. At Lechlade (2), one of the ditches flanking a track shows faintly in comparison with the other where it intersects a ring-ditch, suggesting that the ditch was cut through a mound, subsequently flattened, leaving traces of only that part of the ditch which penetrated the subsoil. At Kempsford (7) a ring-ditch is seen in a space relatively free of ditched features and approached by apparent tracks (Plate 60). The suggestion here is very strong that a mound still stood at one side of the open space, although at some time the ditches of rectangular features impinged on its S.W. side.

Circular or penannular crop-marks with exceptionally broad ditches suggestive of recutting occur at Lechlade (6) and at Kempsford (6–7). A circular ditch of this kind in the area of another settlement at Lechlade (5) proved under excavation to be Roman in date and of uncertain purpose.

Small penannular or semicircular features, about 30 ft. in diameter and with very narrow ditches, dispersed among linear ditches at Fairford (5) and Lechlade (8), and clusters of similar crop-marks at Lechlade (2) and (6), Kempsford (6) and Great Rissington (2), may represent the sites of circular houses. The patterns are comparable with those of unploughed Iron Age hut-circles at Hod Hill in Dorset (Dorset, III, 263–5).