MDE20814 - Possible World War Two training earthworks on Thornworthy Common (Monument)

Two linear groups each of four irregular mounds or small areas of cleared vegetation were noted on aerial photographs. Possibly associated with World War Two training activities. [1,2] Hollows (World War 2 Mortar Emplacements?) SS 7146 4485. Two linear groups of four irregular mounds, or small areas of cleared vegetation seen by McDonnell on aerial photographs [2]. Thought to be possibly associated with World War Two training activities. SS 7151 4474. Seven small subrectangular embanked hollows. Set into a gentle north facing slope which is predominantly heather covered but has a scattering of bracken and rough grass, these hollows are almost obscured by the vegetation. They form two groups each aligned almost due north to south. The first group of four (A to D) is centred at SS 7148 4483 and the second group of three (E to G) is centred 250 metres to the south at SS 7154 4462. The hollows, or small pits, are all orientated northwest to southeast and average 4 metres by 3 metres metres internally and about 0.4 metres deep. The excavated material has been deposited mainly around the lower downhill northern sides to form crude banks. There are no definite entrances evident apart from 'E' which has an angled approach on its northwest side. Hollow 'G' has about 3 smaller rectangular hollows close by on its southwest side. No trace was found of an eighth hollow to the southwest of 'G' noted by McDonnell on the aerial photographs. The exact purpose of these hollows is not clear but they are not of any great age. Their form, situation and layout suggest they are military in origin and function and are probably mortar emplacements possibly used for training purposes during World War Two. Surveyed at 1:2500. Details of hollows: A. SS 71475 44903 4 metres by 3 metres, 0.4 metres deep B. SS 71476 44880 4 metres by 2 metres, 0.4 metres deep C. SS 71476 44860 4 metres by 3 metres, 0.4 metres deep. Probably best preserved. D. SS 71479 44835 4 metres by 3 metres, 0.3 metres dep. Barely discernible. E. SS 71545 44656 4 metres by 4 metres, 0.2 metres deep. Northwestern entrance? Poor bank. F. SS 71537 44616 5 metres by 3 metres, 0.5 metres deep. G. SS 71544 44583 4 metres by 3 metres, 0.3 metres deep. [3] The eight hollows are clearly visible on aerial photographs taken in 1946-8 by the Royal Air Force. There are other features that appear similar in form to the southwest and east. [4] This record was enhanced as part of the National Record of the Historic Environment to Exmoor National Park Historic Environment Record data transfer project. [5] Eight of the hollows were noted during field survey following a wildfire in 2022 and were noted to be visible on aerial photographs dating to 1946. Their details were described as below: A. SS 7147 4490. A rectangular hollow measuring 3 metres east to west, 2 metres north to south and 0.6 metres deep, with a small rectangular slot to the northwest; B. SS 7147 4487. A rectangular hollow measuring 3 metres east to west, 1.5 metres north to south and 0.6 metres deep, with a small rectangular slot to the north; C. SS 7147 4486. An amorphous hollow measuring 2 metres east to west, 1.7 metres north to south and 0.4 metres deep, with a small rectangular slot to the northeast; D. SS 7147 4483. A rectangular hollow measuring 2 metres southwest to northeast, 1.6 metres northwest to southeast and 0.6 metres deep, with a small rectangular slot to the northeast; H. SS 7153 4455. A square hollow measuring 2.2 metres north to south, 2.2 metres east to west and 0.4 metres deep; G. SS 7154 4458. A square hollow measuring 3 metres north to south, 3 metres east to west and 0.3 metres deep, with two rectangular slots to the north and west; F. SS 7153 4461. A rectangular hollow measuring 4 metres east to west, 3 metres north to south and 0.7 metres deep, with rectangular slots to the north and west; E. SS 7154 4465. A rectangular hollow measuring 2.2 metres north to south, 1.7 metres east to west and 0.4 metres deep, with small rectangular slots to the west and northwest. [6]