Purton – Before 1066

In May 1940 Germany invaded France. British troops in France retreated to the channel coast and most of the British Army was evacuated from Dunkirk but left most of their equipment behind. France quickly surrendered and there was a real danger that Britain would be the next target for invasion. General Ironside was given the responsibility of organising Britain’s defences. The first line of defence was along the coast but further inland a series of stop lines was envisaged that could halt the German advance if they broke through the coastal defences. These stop lines consisted of natural barriers and constructed defences. One stop line ran along the Thames upstream from London and along the Avon upstream from Bristol. Unfortunately, there is a gap between the two rivers and this gap was plugged by a defensive line (GHQ stop line red) running from Great Somerford on the Avon to Lechlade on the Thames, then further on to Tilehurst near Reading. Part of this gap was defended by an anti-tank ditch and pillboxes. The anti-tank ditch ran from just north of Wootton Bassett to the River Ray at Mouldon Hill in Swindon. Additional defensive support was provided by seven pillboxes along the route with an additional pillbox situated just north of Blunsden station.

Fig 1 Pillbox, north of Lydiard Millicent, west of Manor Hill Farm

Fortunately, the defensive line was never tested and after the war the ditch was filled in. Of course, the material from the ditch didn’t go back in completely and there was a hump where the ditch had been. Most landowners waited for the hump to settle but some spread the hump out to make the ground flat. The hump can still be seen in many places along the route but in some places the line of the ditch is marked by a slight dip where the hump was bulldozed and settling occurred afterwards. Pillboxes had been constructed to withstand direct hits from tanks so were extremely difficult to demolish, so most were simply left alone.

The route has been studied before and around 2000 two complementary articles were published, one in the Lydiard 2000 magazine by Michael Saunders and one in the Purton Historical Society by Eric Tull. The article by Eric Tull had a map of the route. I wanted to see if there are still any visible remains of the ditch today (2023). Before starting out in the field I examined LIDAR images of the area. LIDAR provides an accurate image of the ground surface by surveying from a light aeroplane. The big advantage of LIDAR is that an image can be produced of the ground surface without vegetation so that it often reveals features that are not visible to the naked eye. LIDAR images are readily available from lidarfinder.com but I used images that used DEFRA data downloaded to ArcGIS. DEFRA is a government agency that originally used LIDAR data to assess flood risks but is now available for most of the country. ArcGIS is a software package for processing and displaying geographical information.

Some sections of the ditch show very clearly on LIDAR

Fig 2 In this LIDAR image the ditch starts in the bottom left hand corner and heads north-east, crossing the Flaxlands road, going through the stable yard before skirting Frith’s copse.

From the LIDAR images I was able to construct these maps of the route:

Fig 3 Route of the ditch from LIDAR images (Southern section)

Figs 4 Route of the ditch seen by LIDAR (Northern section)

However, there were some areas where the route of the ditch wasn’t clear. But another source of data has recently become readily available. The National Library of Scotland publish several different versions of Ordnance Survey maps on their website, maps.nls.uk , not just for Scotland but for the whole of the UK. Recently that have also published aerial photographs, joined together to form a continuous picture. Currently they cover mainly the south east of England. The aerial photographs were mainly taken just after WW2 when the RAF had surplus planes and surplus pilots. For the area we are interested in the photographs appear to have been taken after the ditch was filled in but it is still very visible.

Fig 5. Aerial photograph from the post-war period. The ditch showing in the area north of Lydiard Millicent. Pillboxes show as white spots. In the top right hand corner the ditch touches the edge of the cricket ground

The aerial photographs can now be used to complete the map of the route of the ditch.

Fig 6 Route of the Ditch (Red line) and position of pillboxes (Purple dots)

Update Oct 2023. Since I first published this blog more aerial photographs have been made available on the Historic England website and those taken by the USAF in 1943 have shown that, at the south west end of the ditch it continued to the railway line to about the same place as the M4 crosses it now. The M4 building work obliterated the last section of the ditch. The complete picture now looks like this:

So what can we see today? Obviously, the pillboxes are the most visible remains but there also remains where the ditch crossed a road. Rather than dig up the road, a roadblock was created using concrete blocks and after the war these blocks were simply pushed to the side of the road, where amazingly many still remain. These are near The Fox:

Fig 7 Concrete blocks used as anti-tank measures

And there are four on the ramp leading up to Bremhill Bridge:

Fig 8 One of the concrete blocks used as a roadblock on the approach to Bremhill Bridge

But, what of the ditch itself? This photograph was taken from Flaxlands Lane looking south and the hump of the ditch can be clearly seen in the foreground.

Fig 9. The hump of the filled in ditch near Flaxlands Lane

Other places where the hump can be clearly seen are at the bottom of Flaxlands Lane in the field below Flaxlands Farm where the line of the ditch runs parallel to the road, and in Mill House field between Stone Lane and Purton where the line of the ditch runs diagonally across the field.

The archaeological remains of GHQ Stop Line Red are an important reminder of the impact of WW2 on a quiet corner of North Wiltshire. There are other reminders and these will be explored in future Blog posts.

Keith Allsop March 2023

Further Reading:

Wills, H (1985) Pillboxes, A Study of UK Defences 1940. Leo Cooper/ Secker and Warburg, London

NLS Maps – this link takes you to the page where you can view the photographs https://maps.nls.uk/geo/find/#zoom=5.5&lat=55.20597&lon=-2.98946&layers=11&b=1&z=0&point=0,0

Historic England – this link takes you to the page where you can view photographs https://historicengland.org.uk/images-books/archive/collections/aerial-photos/

Ringsbury Camp is an Iron Age hillfort near Purton in Wiltshire. As far as I am aware it has never been excavated or surveyed, so we know very little about it. However, it is well preserved, and features not visible to the naked eye are visible on LIDAR images. It sits on a bed of Corallian limestone and this can be seen at the entrance in the south eastern corner of the hillfort.

The hillfort (red dot on the map) is easily accessed by a short walk from Purton. There is a footpath that skirts the southern perimeter of the hillfort, but there is no public access to the rest of the monument.

Hillforts come in all shapes and sizes and it is unlikely that all hillforts had the same function. One proposed function of hillforts is that they were concerned with the management of animals. Most hillforts were built in the period 800 – 400 BC and this period coincided with a climatic downturn with prolonged periods of colder and wetter weather, and hillforts could have been built to protect sheep from winter storms (see Climate Change and the Iron Age on this website, https://before1066.com/climate-change-and-the-iron-age/). There is evidence from the LIDAR image that Ringsbury Camp had other roles to play in the management of sheep.

To the north of the hillfort are two annexes; annexes are a common feature of Iron Age hillforts and are generally believed to be connected with stock management. There is access to each annex from the hillfort ditch via a gap in the outer bank. At these points of access, the ditch is frequently waterlogged.

Also on the LIDAR image near the north west entrance is an additional bank and ditch that extends from the western entrance to the first annex.

On the south side of the hillfort the public footpath runs along the top of the outer bank and has worn a groove in the bank.

Where the Mud Lane footpath joins the fort there is an accumulation of loose stone.

My (very rough) diagram shows the features a little more clearly.

My hypothesis is that sheep approached the hillfort from the east along Mud Lane. Where Mud Lane joins the hillfort the accumulation of loose stone indicates that the bank of the hillfort may have been faced with stone and this has collapsed thanks to the action of tree roots. The sheep went up the incline to the top of the outer bank and followed the footpath around to the western entrance. The action of the sheep has worn a groove in the top of the bank.

When the sheep got to the western entrance the sheep were sorted. Some went into the waterlogged section of ditch which could have been a sheep-wash. Some went through the sheep-wash and exited into the first annex and some exited into the second annex. There is also a route around to the first annex that avoids the sheep-wash. So why were they being sorted? There several possibilities:

Sorting the sick from the healthy
Sorting pregnant from the non-pregnant
Sorting by owner; if the sheep were marked in some way the flock could have sheep from several owners
Sorting by the quality of the wool; castrated rams produced the best wool

I am sure there are other reasons why the sheep would have been inspected and sorted, but it does seem that the sorting process is a good explanation for the observed landscape features.

A different LIDAR image , supplied by Phil Barrett, shoes some additional features not evident in the image above.

The larger, second annex appears to have a route around the hillfort to the eastern entrance. So, animals sorted into this annex could return safely to the interior of the fort. The theory that the enclosures on the north side are indeed annexes is confirmed by the 1744 Enclosure Map of Purton (a copy of which can be seen in Purton Museum).

This map clearly shows Great Ringsbury and Little Ringsbury with two entrances between them, so confirming the structure proposed from the LIDAR images.

There is other evidence that Ringsbury Camp is concerned with the management of sheep. The sheep probably spent time away from the hillfort and were brought to it for the processes described above. One possible location would be Purton Common. The road leading from Purton Common towards Ringsbury Camp is known as Hogg’s Lane. Today a hog is usually a word used for a pig but it is also a word for a one-year old sheep, Hogg’s Lane could be the route taken when the young sheep were being moved to the hillfort.

For more about climate change and the Iron Age go to https://before1066.com/climate-change-and-the-iron-age/ . This was my dissertation for the MSc in Applied Landscape Archaeology at Oxford Continuing Education Department.

I have recently (Nov 2023) identified additional features outside the hillfort.

To the north of the annex there are several hut circles clearly visible in green against a parched background, indicating the presence of the ditches which are a feature of Iron Age huts. The rest of the field and an adjacent field also show the possible presence of features but they aren’t quite as clear cut.

However these crop marks can also be created by agricultural activity and circular animal feeders could produce similar markings in aerial photographs. The site seems worthy of a geophysical survey to establish the extent of a possible Iron Age settlement.

Acknowledgements:

The first LIDAR image was created by downloading data from the DEFRA site and uploading to ArcGIS The second LIDAR image was supplied by Phil Barrett

The photograph of the waterlogged ditch is my own.

The aerial photographs came from ARCHI UK https://www.archiuk.com/

A copy of The 1744 Purton Enclosure Map is on display in Purton Museum but if you need more information on this map you may contact me using the website contact details

Before 1066

Pillboxes and Anti-Tank Ditch between Purton and Royal Wootton Bassett, Wilts

Ringsbury Camp, an Iron Age Hillfort near Purton, Wiltshire