Archaeological excavations on land at Rochester Airport
This report presents a summary of the discoveries made during investigations at Rochester Airport by the Canterbury Archaeological Trust between August 2021 and January 2022. The archaeological works were conducted on behalf of Medway Council in advance of the development of a business park at the former airstrip. The scheme covered two separate developments (Fig. 1). The Northern site (centred NGR 574300 164675), situated off Laker Road and covering an area of approximately 11 hectares, was subject to archaeological strip, map and sample excavation. The Southern site (centred NGR 574680 163800) was monitored as part of an archaeological watching brief.
[fg]png|Fig 1 Site location.|Image[/fg]
Previous investigations at the Northern site included a geophysical survey which yielded mixed results reflecting potential features of archaeological origin, modern features and a broad scatter of ferrous noise (WSP 2021, 13). Subsequent archaeological evaluation in this area revealed evidence for pits, ditches and post- holes dated late Bronze Age to early Iron Age, as well as limited evidence for Roman period activity (Pre-Construct Archaeology 2021, 5). Evaluation of the Southern site showed that previous development in this area had significantly reduced the potential for the survival of archaeological features or deposits (ibid.). These findings were upheld by the results of the archaeological monitoring conducted as part of this project.
Archaeological and historical background
Evidence for prehistoric activity in the wider area is currently poorly represented, although some evidence ranging in date from the Mesolithic period through to the Iron Age has been recorded a short distance to the west at Little Monk Wood (Mosley and Holman 2014, 7). To the east of the airport, the present A229 Maidstone Road is thought to follow the route of a Roman road which connected Rochester and Maidstone (Margary 1955, route 13). A compacted gravel surface thought to represent a section of this road was recorded by the Lower Medway Archaeological Research Group in 1962 (KCC HER No. TQ 76 SW 71). To the west of the present site, a Roman inhumation burial accompanied by two vessels was discovered in 1913 (Mosley and Holman 2014, 8). Recent investigation of a site situated approximately 500m to the south-east of the present site, revealed evidence for late Bronze Age activity, and Iron Age enclosures and settlement (Pre-Construct Archaeology 2021, 13). Late Iron Age to early Roman activity was also [pg355][pg356]recorded, evidence for which included the remains of an early Romano-British masonry enclosure wall (ibid, 14).
Nearby Rochester would have been an important centre during the early medieval period, and in the seventh century AD the cathedral was founded (Everitt 1986, 76). Beyond the limits of the town, the nearest settlements to the airport site, as recorded in Domesday Book, were Little Delce, Great Delce and Nashenden (Mosley and Holman 2014, 8). The manor of Horsted, possibly twelfth century in origin, gives its name to the area and the later fort to the east of the site. The manor was granted ‘a charter of free warren’ in 1248 (Hasted 1798), the location of which is perhaps recorded on the Tithe map with ‘Warren Wood’, situated 300m north of the site (Mosley and Holman 2014, 8-9). Cartographic evidence suggests that the site formed part of Boxley Wood during the eighteenth century but by the early nineteenth century, large areas had been cleared to create farmland (ibid, 9). The parish boundary between Rochester St Margaret and Chatham, which crosses the Northern Site, is recorded on the Tithe map of the area.
During the nineteenth century, the Chatham Ring Fortress was developed. This defensive emplacement, built for the protection of the Naval Dockyard at Chatham, comprised an arc of seven forts running from Twydall to Borstal (KCC HER No. TQ 76 NE 398). Situated to the north-west and north-east of the site were Fort Bridgewoods and Fort Horsted respectively. Fort Bridgewoods was constructed in 1884 and Fort Horsted between 1860 and 1889. However, due to rapid advances in artillery techniques and hardware, the forts were obsolete almost as soon as they were completed. During the First World War, Fort Bridgewoods was used as a barracks. Fort Horsted was abandoned by the military as a defensive site in 1906-7 but continued to serve as an ammunition store (Mosely and Holman 2014, 9). Development at the site began during the early 1930s, when the Rochester Corporation acquired over one hundred acres of arable land for the development of a municipal aerodrome. Local aircraft manufacturers Short Brothers (Rochester and Bedford) Ltd quickly sought to lease the site and became involved in the establishment of the airfield. In 1934, Shorts submitted their Report on [a] Proposed Site for Permanent Use which provided a description of the topography of the site at that time as ‘at present part pasture and arable land – the broad back of a ridge rising from north to south’. The report went on to state that holes had been infilled and ‘sharp ridges levelled and rough places made plain’, testimony to the levelling and modifications made to the site’s landscape at this time (Mosely and Holman, 11).
In 1937 the Air Ministry approached Short Brothers to manage a flying school at the site, and the airport was subsequently extended to the south to accommodate this. The airport now consisted of three runways, the Shorts factory, a factory for Pobjoy Air Motors Ltd, along with several hangers constructed for the flying school. Production of the Stirling Bomber began at the site in 1939 (ibid, 13-15). With the prospect of the Second World War, efforts were made to camouflage the airport; factory buildings were painted to resemble farm buildings and the airfield painted to look like fields (Collyer 1988, 428). As an additional defense measure, a dummy airport was constructed at Lidsing located 4km to the south-east (ibid.). In 1940, the defense of the airfield and factories fell to the thirty-third Battalion of the Kent Home Guard who were based at Fort Bridgewoods. A light anti-aircraft [pg357]battery was located at the fort, and Fort Horsted was used as an anti-aircraft gun-emplacement and observation point (Mosely and Holman 2014, 15). At the site, tube mines were laid beneath the airstrips; these were intended to be detonated should enemy aircraft land (MacDougall 1981, 151). On 15 August 1940, the airfield was bombed. Five Stirlings in the main assembly hanger were destroyed, and one member of the fire service lost his life (ibid, 156). After the war the Short Brothers left the airport, but the Training School returned until 1953, commercial flight resumed and a civilian flying club was formed (Mosely and Holman 2014, 17). Currently the airfield continues to operate as a civil airport.
Results of the excavation (Figs 2-3)
[fg]png|Fig 2 Detail of northern area of site.|Image[/fg]
[fg]png|Fig 3 Detail of southern area of site.|Image[/fg]
The preservation of archaeological remains at the site was poor. Clearance of woodland to make way for arable land-use during the post-medieval period may have caused some ground disturbance. However, the greatest impact was almost certainly during the development of the site as an airfield in the 1930s, when the entire area was truncated and levelled. In addition, the bombing of the airfield during the Second World War, and the installation of wartime defences including tube mines, had a further impact. It is likely that some archaeological features were destroyed as a result of this disturbance, and of those recorded only the basal remains survived. Cultural material was very scarce and, coupled with a lack of stratigraphic relationships, many features could not be confidently dated. Due to the wartime history of the site, an unexploded ordnance survey was carried out prior to the archaeological excavation.
Mesolithic, Neolithic and Bronze Age
A small assemblage of Mesolithic and early Neolithic worked flint was recovered. However, no features of this date were identified and low-level activity during these periods is indicated. The flint assemblage was recovered from a range of later features widely distributed across the site. Post-medieval features, and the fill of a late Iron Age to early Roman ditch, produced two scrapers and one knife of early Neolithic date. In addition, a short linear feature [20020] probably post- Roman in date, produced an interesting early Neolithic group including a backed knife, an end retouched scraper, a retouched flake, and a notched flake. The close association of the latter group of objects may indicate that they were derived from a disturbed earlier feature located nearby.
Situated within the southern part of the site, one isolated pit [8046] has been dated to the early Bronze Age period. This sub-rectangular feature produced several fragments of a possible long-necked Beaker dated 2000 to 1500 BC. The pot had been decorated with horizontal combed decoration, with panels of combed and plain zones in addition to shallow impressions possibly created using a bird bone (McNee 2022, 4). This was the only vessel represented in this feature and may have been originally deposited in a complete state. However, the function of the feature is uncertain; the cut appears too irregular for a grave and no other finds were recovered.
Central to the site, another isolated feature of Bronze Age date was recorded.[pg358][pg359][pg360]This large pit [1073] produced a small assemblage of worked flint which included a group of struck flint flakes all derived from the same knapping episode. The pit also produced an assemblage of charred plant remains comprising wheat (Triticum), barley (Hordeum vulgare), hazelnut shell (Corylus avellana) and a small quantity of wild plant/weed seeds. Barley grains recovered from the primary pit fill returned a radiocarbon date of cal BC 1737-1540 (at 2 sigma 95.4 per cent probability; UBA-51813; 3357 +/- 28 BP; intcal20.14c (Reimer et al. 2020)), indicating a middle Bronze Age date.
Later Bronze Age and Early to Middle Iron Age (c. 1100–350 BC)
Activity represented by a cluster of features dated to the late Bronze Age and earliest Iron Age period was recorded towards the eastern limit of the site (Fig. 3). Here, a large sub-circular pit [3010] produced an assemblage of pottery dated 1100-600 BC (Plate 1). The pottery assemblage was mixed throughout the fills, with several large sherds surviving; some with soot present on the interior. In addition, four possible loomweight fragments were also recovered and a small quantity of daub. Rare, charred plant remains included wheat and wild plant/weed seeds.
Eight smaller pits [1038], [2015], [3022], [6029], [8014], [13005], [16003] and [17008] were situated nearby. Pit [1038] produced a large assemblage of pottery of early to middle Iron Age date. Wheat grain and chaff, and barley grains were also recovered from this feature, and radiocarbon dating of wheat grains returned a date of cal BC 1041-840 (at 2 sigma 95.4 per cent probability; UBA-51811; [pg361]2797 +/-28 BP; intcal20.14c (Reimer et al. 2020)). Another pit [16003] contained the basal remains of a single vessel dated 800-400 bc (Plate 2). The vessel was probably complete when it was placed in the pit, and just over 3.6kg of heat- affected greensand fragments were found in situ within the vessel base. Pottery of similar date was also recovered from pits [2015] and [17008], along with two further features which were recorded during the evaluation stage (Trench 50; Pre- construct Archaeology 2021, 31).
[fg]jpg|Plate 1 Pit [3010] showing large pottery sherds lying on the base.|Image[/fg]
[fg]jpg|Plate 2 Pit [3010] showing large pottery sherds lying on the base.|Image[/fg]
To the north-west, a large polygonal ditched enclosure was recorded [1101]. The ditch had a ‘V’-shaped profile with a surviving maximum width of 2.1m and a surviving depth of 1.1m. The enclosure was not fully exposed within the area of excavation, but an internal area of just over 1 hectare was visible. Very few finds were recovered from the fills of the ditch, but a broad early to middle Iron Age date is indicated. A total of seven small pits and four large pits situated within the enclosure have been attributed to this phase of activity. Of these, features [1006] and [2085] produced small quantities of pottery dated 600-100 BC. Pit [9046] was notably different in character, being infilled with alternate deposits of charcoal and burnt flint. In total, flint weighing approximately 93kg was recovered from this feature.
Elsewhere a scatter of pits, post-holes and small features dated to this phase were found across the site. Most features produced small assemblages of pottery. However, pit [14023] located in the central southern area produced a large assemblage of early Iron Age pottery along with charred plant remains which [pg362]included barley. To the east, pit [18015] produced pottery of similar date alongside wheat grains and chaff.
Late Iron Age to Early Romano-British (c. 100 BC – AD 100)
Perhaps towards the end of the middle Iron Age or during the later Iron Age period, the boundary ditches of the polygonal enclosure were recut [1054]. The interior of the enclosure may also have been modified around this time, with the addition of two ditches each aligned north-east to south-west [3001] and north-west to south-east [2001].
A group of coaxial boundary ditches [1080], [2006], [6087] and [20003], situated 200m to the south-east of this enclosure, may also have been established around this time. Aligned north-east to south-west and north-west to south-east, these ditches appear to represent the establishment of rectilinear field plots. Gaps between the ditches may have allowed transit between the fields, and a larger gap located at the western corner of ditches [2006] and [6087] would appear to represent a wider entrance.
In this area, a large rectangular pit [9097] with an associated post-hole was recorded. This produced residual earlier Iron Age pottery and several sherds of late Iron Age to early Roman date (mostly 25 BC – AD 60). Cereal remains recovered from this feature produced evidence of hulled wheat including spelt (Triticum spelta). A smaller pit [11033] situated to the west, produced pottery of a similar date, in addition to spelt, free-threshing wheat (Triticum aestivum/turgidum), an oat (cf. Avena) grain, hazelnut shells and wild plant/weed seeds. Wheat grains returned a radiocarbon date of cal BC 46 – AD 116 (at 2 sigma 95.4 per cent probability; UBA-51812; 1992 +/-31 BP; intcal20.14c (Reimer et al. 2020)). A scatter of other pits in this area all produced pottery dated 25 BC – AD 50.
Romano-British (c. AD 43–410)
There was no evidence to indicate that the polygonal enclosure was maintained into the Roman period. Following the recutting noted above, the ditches probably silted-up gradually and finds recovered from the fills were sparse but included fragments of poorly preserved mammal bone (pig/sheep/goat) and one fragment of tegula. The latest pottery recovered from the ditch fill has been dated AD 43-100. Similarly, the ditches situated within the interior of the enclosure were probably left to silt-up, and pottery recovered from ditch [2001] has been dated AD 70-250. The group of boundary ditches located at the south-east also appear to have infilled gradually, the fills of which produced residual Iron Age pottery and later material dated 25 BC – AD 70. Evidence for recutting was observed in one ditch [6087], however. The fill of the earlier ditch produced small quantities of hulled wheat including spelt, along with cattle bone and pottery dated 25 BC – AD 100, whilst pottery recovered from deposits in-filling the recut, provide a potentially later date of AD 43-230. Nearby a large possible quarry pit [8058] has been tentatively attributed to this phase. The feature, measuring 6m x 8m and with a maximum depth of 1.38m, produced pottery dated AD 43-100/150.
At the north of the site, a group of three small hearths [3072], [9116] and [16086][pg363]were recorded. Each had evidence for in situ burning, and analysis of the charcoal indicated that oak was the sole timber selected for use as fuel. Pottery recovered from one hearth has been dated 25 BC – AD 70. A short distance to the north of this group lay another hearth [11063] which comprised a circular setting of flint nodules sealed by a deposit of burnt clay. The flint setting was situated towards one end of an elongated pit which had subsequently infilled with a series of charcoal-rich deposits. The deposits produced pottery principally dated AD 43-100, along with a substantial assemblage of charred plant remains. Spelt wheat was the main cereal represented although emmer, free-threshing wheat, barley and wild oat were all present. Charcoal analysis demonstrated the selection of a range of roundwood of Prunus (cherry type), Maloideae (hawthorn group), hazel and field maple, a mixed assemblage suggestive of a domestic hearth (Challinor 2023, 5). Radiocarbon dating of wheat grains from this hearth have returned a date of cal AD 28-212 (at 2 sigma 95.4 per cent probability; UBA-51814; 1913 +/- 29 BP; intcal20.14c (Reimer et al. 2020)).
Towards the south of the site, a small, isolated hearth [9014] was also recorded. Similar to that of hearth [11063], the base of this feature also comprised a circular setting of flint nodules. Analysis of the charcoal-rich deposit overlying the flint base demonstrated that field maple and Maloideae were the principal fuel types.
Distributed across the site, a total of nine possible cremation burials ([1093], [3032], [5045], [8049], [8097], [15046], [17004], [18054] and [20067]) were recorded. All of the burials appeared to be unurned. Some of these features produced very small quantities of cremated human bone, but this may be due to the degree of truncation across the site. The generally low recovery of cremated remains rendered it impossible to learn more about the age and sex of the individuals. To the north, burial [1093] included iron nail fragments, and charcoal analysis indicated that oak was used as pyre fuel. Oak charcoal was also recorded from burial [8049], whilst ash charcoal was present in burial [8097]. Both of these fuel types are considered suitable for cremation purposes due to the high sustained heat they produce (Challinor 2023, 6). Burial [8097] was also notable in that the remains of a grog-tempered pottery vessel dated AD 43-70 was recovered. Although incomplete and heavily damaged by later disturbance, the vessel may have been complete when originally interred. charcoal from this feature returned a radiocarbon date of cal AD 20-204 (at 2 sigma 95.4 per cent probability; UBA-51810; 1935 +/- 27 BP; intcal20.14c (Reimer et al. 2020)).
Also situated towards the north, possible burial [3032] produced a small quantity of cremated human bone and charcoal indicative of Maloideae and oak. One small fragment of charcoal has a possible worked surface suggesting that an item of worked wood was included in the pyre (Challinor 2023, 3). To the south, the burials were more widely distributed. A pair ([15046] and [17004]) were recorded towards the east of the site and the remainder loosely scattered. The use of ash and oak pyre fuel was identified in burials [18054] and [20067] respectively. Iron nail fragments were recovered from burial [18054] and radiocarbon dating of charcoal returned a date of cal AD 27-208 (at 2 sigma 95.4 per cent probability; UBA-51808; 1921 +/- 28 BP; intcal20.14c (Reimer et al. 2020)).[pg364]
Early medieval to medieval (c. AD 410 –1540)
Only one feature can be confidently attributed to this phase of activity. Hearth [20032], situated towards the south of the site, produced residual Iron Age pottery and oak charcoal. The latter of which has been radiocarbon dated to cal AD 661-820 (at 2 sigma 95.4 per cent probability; UBA-51809; 1283 +/- 30 BP; intcal20.14c (Reimer et al. 2020)).
A scatter of small pits and post-holes were recorded which, based on limited stratigraphic relationships, might be of medieval date. However, there is insufficient evidence to state this with any certainty. A total of six sherds of thirteenth- to fourteenth-century pottery recovered from an earlier feature located towards the north of the site were almost certainly intrusive.
Post-medieval (c. AD 1540 –1901)
A large proportion of the features identified date to the post-medieval period. In several areas, pairs of parallel wheel ruts were identified. Whilst evidence for formal man-made trackways such as metalled surfaces was not observed, repeated use of these alignments was indicated, suggesting that they represent regularly used routes.
Pits and post-holes of post-medieval date were distributed across the site, but their function is uncertain. However, one north to south fence alignment was identified, situated towards the east of the site and indicated by a group of post-holes.
Three irregular quarry-like features were also identified; situated towards the north of the site features [1097] and [6142], and to the south [11055]. The fills of these features produced very little dateable material but a nineteenth or early twentieth century date is indicated.
Modern (c. F 1901– present)
Modern disturbance was represented by a scatter of small features and a live electricity service. Features almost certainly relating to Second World War activities were also identified, and one decommissioned tube mine was recovered during the unexploded ordnance survey.
Discussion
The results of these investigations suggest that activity at the site increased from the late Bronze Age period. Prior to this low-level, perhaps periodic, visits to the site are represented by the Mesolithic and early Neolithic flintwork, and the early and middle Bronze Age features. At present there is little evidence of occupation during these periods in the wider area, and these discoveries add to the current understanding of activity and settlement during these periods around the Medway Valley.
By the late Bronze Age/earliest Iron Age period, a settlement may have developed nearby. The cluster of features recorded at the east of the site could potentially lie on the periphery of a settlement area located further to the east beyond the site limits. cultural material recovered from these features including large sherds of [pg365]pottery, loom-weight fragments and cereal remains support the notion that domestic activities including food processing, cooking and weaving are represented. Whilst the unusual deposition of a vessel containing burnt stone could be interpreted as representative of ritual activity. Similar examples of vessels containing burnt stone have been recorded in Sussex and Hampshire, for which this interpretation has been proposed (Seager Thomas 2010, 360-361).
To the west of the site, the large polygonal enclosure may be contemporary with this activity. Dating for the establishment of this enclosure is uncertain, but early to middle Iron Age pottery recovered from the ditch fills indicates that the boundary was infilling after this time. To the interior of the enclosure, a scatter of small features was recorded but there was no clear evidence of any structures, and it is uncertain whether a settlement and/or agricultural fields were enclosed. However, the recovery of cereal remains comprising wheat (emmer and spelt) and barley would support evidence for crop production taking place in the area around this time. After a period of silting up, the polygonal enclosure ditch was recut and the land to the interior of the enclosure was subdivided by the addition of boundary ditches.
Probably during the later Iron Age to early Roman period, a series of rectilinear enclosures were established a distance to the south-east of the polygonal enclosure. These enclosures probably represent a series of fields, and charred plant remains recovered from contemporary features suggest the continuation of agricultural practice in the area. Interestingly, analysis of the plant remains revealed evidence to indicate a shift towards a preference for spelt production during this period; a trend which has been noted elsewhere in Kent (Giorgi 2023, 4). In addition, whilst the preservation of bone at the site was very poor, fragments of cattle teeth and mammal bone (pig/sheep/goat) recovered from the fills of these boundary ditches may provide some evidence for animal husbandry.
Agricultural activity in the area appears to have continued into the Roman period. Whilst the polygonal enclosure may have fallen out of use, evidence suggests some maintenance of ditches in the south-east group of enclosures. Beyond these fields, the land to the north and west may not necessarily have served an agricultural function. Two hearths (9014 and 11063) associated with this period, each with a purposely built flint base, were recorded. Charcoal recovered from these features revealed that a range of wood types were used for fuel, suggesting domestic use. Any evidence for structural remains which might be associated with the hearths was, however, lacking.
The remainder of the hearths (3072, 9116 and 16086) were different in character, being clustered together and notably demonstrating the use of only one fuel type, oak. A preferential selection of oak and ash for pyre fuel has also been identified, and it is tempting to suggest that the hearths were associated with funerary activity in this area. In total, nine unurned cremation burials were recorded. Although perhaps interred in an organic container such as a bag or box, there was little evidence of grave goods, except for one burial which was probably accompanied by a pottery vessel. Two burials were also found with iron nail fragments, and a small fragment of burnt worked wood was recovered from a third. These latter items could relate to a coffin, funerary structure, or a grave good that was included in the cremation process.
[pg366]The hearth of Anglo-Saxon date appears to be the only evidence for activity in this area at the time, although it is possible that some of the undated features could be associated. The recovery of thirteenth- to fourteenth-century pottery may be indicative of manuring rather than any settlement-related activity and there is currently very little evidence for activity throughout the medieval period in the area. Cartographic evidence indicates that the area was woodland by 1769 (Mosley and Holman 2014, Fig. 4). Post-medieval activity in the form of woodland clearance and subsequent agriculture is represented by wheel ruts and other features, including one fence line which appears to pre-date the construction of the airfield.
Overall, the activity recorded at the site appears to represent the development of an agricultural landscape established during the late Bronze Age/early Iron Age period. There is some evidence to suggest settlement beyond the eastern limit of the site at this time. The agricultural activity continued into the later Iron Age to early Roman period and was likely contemporary, and associated with, the settlement area recorded to the south-east of the site. Later, during the Roman period, the cremated remains of individuals were interred. This dispersed cemetery perhaps indicating the limits of the settlement and its land at this time.
Acknowledgements
This report includes contributions by Adrian Gollop, Enid Allison, Luke Barber, Chris Butler, Jon Giorgi, Malcolm Lyne, Barbara McNee and Andrew Richardson and Adelina Teoaca. The archaeological programme was initiated by Medway Council. Ben Found monitored the project on behalf of Kent County Council Heritage Conservation Group. Ray Kennedy of WSP Cultural Heritage and Archaeology Team acted as consultant to Medway council.
Tania Wilson
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