Port Meadow, in the north-west corner of Oxford by the River Thames, is a 300-acre floodplain that has been pasture for approximately 1,000 years, if not longer. The land is scattered with Bronze Age burial mounds and evidence for Iron Age settlement, and the site has been a Scheduled Ancient Monument since the 1970s. While this listing (www.historicengland.org.uk/listing/the-list/list-entry/1010717) documents many of the meadow’s prehistoric features, it fails to mention that it also contained a First World War flying training aerodrome at its northern end, near Wolvercote. This was not a small complex to ‘forget’: built in early 1916, by 1918 the site accommodated more than 800 trainees and personnel, with more than 60 aeroplanes using 11 hangars and other largely temporary buildings. But after the aerodrome buildings and structures were sold and dismantled in 1920, all obvious traces of it vanished and its story largely faded from collective memory.
Today, the meadow – an important ‘green lung’ for Oxford – is more frequently visited by dog walkers, fishermen, and other leisure seekers. But in 2015 the Wolvercote WWI Aerodrome Memorial Project was set up to raise awareness of the locale’s less well-known heritage, and to erect a stone memorial to the 17 airmen who were killed in flying accidents while training on or visiting the meadow between 1917 and 1918 (nine are buried locally). This latter aim was achieved thanks to funds raised by public subscription, and the memorial and information board were unveiled in May 2018 – the centenary of the death of one of the pilots. The community project’s remaining funds were then dedicated to carrying out a survey to see whether anything survived of the aerodrome below ground.
The complex’s appearance was not a mystery: aerial photographs from 1918 provided a detailed layout of the buildings when they were still standing, but we wanted to establish if anything remained beneath the surface. Even though it looks the same, there is a difference between a field where there had once been something, but now has nothing, and the same field where people know there are surviving remains, even if they cannot be seen. So how should our investigation proceed? No traces of the demolished aerodrome buildings are visible in modern aerial photographs, only a small concrete shelter – which was erected to the east of the main building complex as a refuge to protect the ground crew who set up nearby targets for aerial bombing and shooting practice – and the line of the access track could be seen in these images. LiDAR also failed to show any sign of the main complex, and excavation was not a practical option due to the site’s scheduled status. It was deemed too risky to potentially fragile remains, as well as being beyond the community group’s means. With these avenues quickly exhausted, geophysics looked like our best and probably only option.
Echoes of the aerodrome
The project did not have the happiest start: it was shaken by the untimely death of Alister Bartlett, the original surveyor appointed and one of the drivers of modern magnetometry, who had a great depth of experience and was generous in sharing it. In his place, my wife Sally and I, both of Abingdon Archaeological Geophysics, were asked to see what could be done. With the necessary Historic England and landowner consents obtained for the survey, we were able to proceed over September and October of last year.
What were we looking for? Images from 1918 show that the aerodrome hangars were Bessonneau-type tents – canvas over a timber frame, not unlike frame tents from the 1970s, but larger and less colourful – each of which could accommodate up to six aeroplanes. There had also been standard army sectional wooden sheds dotted around the complex, used for instruction and administration, and a large rigging shed (specifically, an RFC 1915 Pattern Flight Shed) made of corrugated iron, which had stood between the hangars. There had were various bell tents on the site for ground crew, too. As the chances of such ephemeral remains both surviving and being detectable were slight, it was decided to survey a trial area using magnetometry and earth resistance, and then extend the project or give up, as appropriate.
The earth resistance results were quite good, but the magnetometry results were much better than expected – although, at first, we didn’t know why. Initially, we thought that the igneous stone chippings used on the surface of the access track could have penetrated into the features and made them magnetically visible. But, following a couple of conversations, we had our answer. The first discussion was with Peter Smith, chair of the Wolvercote WWI Memorial Project, who mentioned that he had a 1970s recording on a local radio programme in which a visiting airman complained about how dusty it was flying on the site. The other was with the Council’s Port Meadow warden, who told us that the cattle that roam the meadow had created hollows to act as salt licks. After examining one of these, we found it had about 10cm of ash and clinker in its side.
It appears that the City Council had used these materials for the access track, pathways, and hardstandings when they were asked to assist with the aerodrome construction over a century ago. This was common until the use of coal, especially low-quality nutty slack, declined. Even Oxford’s Iffley Road running track, where Roger Bannister broke the four-minute mile, was a cinder track. This proved lucky for us, as low-quality coal contains silt from when the coal deposits accumulated. When this silt is heated, the iron in it changes into a more magnetic type and becomes magnetically detectable. This dust then blows around and accumulates in all sorts of places. At Port Meadow, some of the highest readings were from what was probably a soakaway that drained the vehicle parking area behind the Flight Shed.
As a consequence, the further the aerodrome buildings were from the main cinder areas, the less detectable they are. Fortunately, someone appears to have put cinders at the entrances to most of the hangars, possibly to provide a firm access ramp onto the flying ground, as well as in the walkways between some of these structures. Other buildings were detected by identifying what are probably bricks used to level their bases, while one hangar was detectable thanks to the pieces of iron which had been left outside it, presumably when it was dismantled in 1919/1920. This serves as a reminder that the remains we locate often reflect the demolition phase of a site as much as its earlier use.
The only main parts of the complex that we could not identify were the bell tents and some of the later hangars, the last four of which were added between May and September 1918. Perhaps by then the site’s occupants had realised that coal ash made life uncomfortable, and they had used either bare earth or some other material to fill puddles.
Finding the firing range
The aerodrome also had a firing range, initially used to adjust and practice with aeroplane machine- guns, and later for small-arms shooting practice. This facility was situated away from the main buildings to the west, close to the River Thames – and, presumably unknowingly, on an area of probable Bronze Age or Iron Age occupation. These prehistoric remains have been known about since R J Atkinson’s note ‘Archaeological Sites on Port Meadow’ in Oxoniensia (1942, p.32), and most are visible on aerial photographs. But our survey has revealed further details. The circular ditches mainly produced high magnetometry readings, which indicates either that they were open long enough to fill with soil which contained magnetic bacteria, or that they had some burnt soil in their fills. One ditch, though, had a low magnetic response, suggesting that it had either been cut into the underlying gravel and had not silted up as much as the others, or it had filled with alluvium (sediment deposits left by floodwater).
The magnetometry was able to find traces of the firing range itself, which showed up as a series of lines, probably made by brick pieces, at either end. These were some 35m apart, probably reflecting the range at which the airmen were being trained to fight. We may also have located a circle used for calibrating aircraft compasses, which is shown in contemporary photos of this area, but were unable to locate an area of concrete nearby. This is not unexpected for concrete without reinforcement and with a limestone gravel aggregate, but it does indicate that there may well be other surviving remains which were not detected and may need earth resistance or other methods to be discerned.
This area yielded some more mysterious findings – for example, pairs of small high anomalies, approximately 5m apart. These may be related to the Second World War anti-glider columns and posts that are known to have supported a network of wires over the meadow. We should know more when we are able to examine aerial photos in the Historic England Archive in Swindon, once they become available again after the COVID-19 closure.
A flying future
What of the future of the site? Hopefully, it will be uneventful; the Scheduling description does need updating to recognise the significant presence of this First World War aerodrome, but the remains have survived by being left undisturbed and we hope this will continue. Areas which are currently damp should be kept damp, and vice versa. Non-invasive investigations, such as further surveys using earth resistance ground-penetrating radar or electromagnetic methods could be done, and research using aerial photos and LiDAR could also prove useful now that we know what we are looking for. Fortunately, we appear to be in the position where scientific techniques may be advancing faster than the remains here are decaying.
The results have also helped put a capstone on the Wolvercote WWI Aerodrome Memorial Project: a fitting commemoration of this phase of the site’s life. As Peter Smith said, ‘I was delighted and relieved to see the extent of features revealed; the survey results add to this local history story that had faded over time, but has more recently been resurrected.’
The survey report has been submitted to the Archaeology Data Service (www.archaeologydataservice.ac.uk) and will hopefully be published soon.
Peter Smith (2019) Oxford’s Lost Aerodrome, Oxfordfolio.
Peter Wright (2015) The Royal Flying Corps in Oxfordshire, Cross & Cockade International.
Roger Ainslie (2020) Archaeology – in the Service of Property Development? Lessons from English archaeological geophysics (e-book).
Wolvercote WWI Aerodrome Memorial Facebook page: www.facebook.com/wolvercoteww1memorial