South Devon Rapid Coastal Zone Assessment NMP Project

Between 2013 and 2014 an archaeological aerial survey of the south Devon coastline was completed by a project team of staff from AC Archaeology and Devon County Council. This used National Mapping Programme (NMP) methods and was commissioned by English Heritage (now Historic England) as the first component of a ‘Rapid Coastal Zone Assessment’ to inform shoreline management as the coastline continues to change. The project was hosted within the Devon County Council Historic Environment Team.

Read more about other aerial survey NMP projects in Devon.

This project covered 414.5 square kilometres of coast and estuary from Plymouth Unitary Authority in the west to the county boundary with Dorset in the east. The winter storms of 2013-2014 aptly demonstrated the risks to the coastal Historic Environment, with a number of archaeological sites revealed, and others destroyed.

Breached sea wall at Sidmouth. AFL EPW013501 June 1925. © Historic England (Aerofilms collection).
Breached sea wall at Sidmouth. AFL EPW013501 June 1925. © Historic England (Aerofilms collection).

Significant damage to the railway line at Dawlish cut off Brunel’s historic rail link to south Devon and Cornwall for 8 weeks, as comprehensively reported in the national press and discussed in parliament. During the survey aerial photographs of a substantial breach in the sea defences at Sidmouth indicate a similar scale of collapse further along the coast in 1925; this was also the subject of parliamentary debate.

The project consulted well over nine thousand hard copy aerial photographs loaned from the Historic England Archive, Cambridge University Collection of Aerial Photography and those held by Devon County Council, as well as lidar data and modern digital vertical aerial photographs, particularly from the Channel Coast Observatory.

A total of 1501 archaeological or historic sites were identified from the aerial imagery and recorded on the Devon Historic Environment Record (HER), available through Heritage Gateway and mapped on the Devon Environment Viewer; those within Torbay will be added to the Torbay Historic Environment Record. Some of the main themes identified during the survey are summarised below, but much more detail is available in the report.

Military defence and fortification

Although prehistoric hillfort defences (e.g. MDV58272) and post-medieval fortifications were recorded, including interesting (but now built over) defences at Sidmouth (MDV14047) and a possible civil war gun emplacement at East Soar (MDV104268), the survey was dominated by Second World War military remains.

‘The Burrow’ at Seaton; lost remains of a multi-period defensive site (MDV14047; MDV106009). AFL 60516 EPW023884 SEP-1928. © Historic England (Aerofilms collection).
‘The Burrow’ at Seaton; lost remains of a multi-period defensive site (MDV14047; MDV106009). AFL 60516 EPW023884 SEP-1928. © Historic England (Aerofilms collection).

The coastal strip was a focus for, and often retains much evidence of, both defensive and offensive activities. A ‘coastal crust’ of anti-invasion defences could be seen on many of the aerial photographs, for which the historic aerial photographs are often the only evidence, the barbed wire, beach scaffolding and ditches having often been removed or levelled soon after the war ended (e.g. MDV105828).

Anti-invasion barbed wire apron crossing the estuarine silts around the docks at The Point, Exmouth. NMR SX 9980/17 MSO 31241/46 14-AUG-41. Historic England (RAF Photography).
Anti-invasion barbed wire apron crossing the estuarine silts around the docks at The Point, Exmouth. NMR SX 9980/17 MSO 31241/46 14-AUG-41. Historic England (RAF Photography).

Structures relating to active coastal and air defence, such as concrete pillboxes, gun batteries and searchlights, were often more enduring.

Similarly, control blocks are often the sole surviving elements of decoy sites, the earthworks and temporary structures that used lights and fire to simulate military targets having been removed as soon as possible to return the land to agriculture.

Particularly significant are a number of surviving pillboxes along the Taunton Stop Line, one of a number of early Second World War inland defence lines throughout the country intended to trap or slow enemy advance in the event of a successful landing.

A range of defensive structures and earthworks fortified the natural barrier of the Axe Estuary. The more durable of these have been well recorded and many brick or concrete structures survive (e.g. MDV39356), but the survey added much more detail on less lasting elements of the defences, such as roadblocks, ditches, barbed wire obstructions and anti-tank blocks. Further to the north a lot of remains have also been recorded in the more recent Blackdown Hills NMP project, particularly around Axminster, and these are especially interesting in conjunction with stories from local people about life in this area during the Second World War.

Heavy machine gun emplacement on the Taunton Stop Line; additional detail on its shape and size was added from the aerial photograph evidence. Photograph: Stephanie Knight
Heavy machine gun emplacement on the Taunton Stop Line; additional detail on its shape and size was added from the aerial photograph evidence. Photograph: Stephanie Knight

At Slapton, the first day of Exercise Tiger, a mock assault on Slapton Sands to train troops for the D-Day landings, has been captured on aerial photographs taken by US forces. These sobering images were taken on the day that 300 allied troops lost their lives in a mis-timed bombardment, and a day before the German U-boat attack in which more than 600 more men were killed.

Mock assault on Slapton Sands as part of Exercise Tiger. US/30GR/LOC41 33 27-APR-1944. Historic England (USAAF Photography).
Mock assault on Slapton Sands as part of Exercise Tiger. US/30GR/LOC41 33 27-APR-1944. Historic England (USAAF Photography).

The photographs show temporary structures such as pontoons (MDV106737) and bridges (MDV106738) as well as landing craft and barrage balloons that do not have a fixed physical position.

Similar D-Day preparations, captured on aerial photographs, were recorded at Braunton during the North Devon AONB NMP survey.

Other training sites have left remains at Dalditch Camp and Holcombe. Military infrastructure such as fuel stores, as well as civil defence sites such as air raid shelters, were frequently recorded in Torbay.

Agriculture and subsistence

In some uncultivated areas, especially along the coast, the remains of extensive prehistoric field systems survive as low earthwork banks. Their good preservation adds to their significance, and some have been protected as Scheduled Monuments. The survey suggests that the field systems in fact extend beyond the scheduled area, for instance at Deckler’s Cliff (MDV15083).

Removed curvilinear boundaries at Axmouth overlain onto the late nineteenth century mapping. NMP mapping © Historic England. 1880s-1890s 25 Inch First Edition Ordnance Survey mapping © Crown copyright and Landmark Information Group Ltd.
Removed curvilinear boundaries at Axmouth overlain onto the late nineteenth century mapping. NMP mapping © Historic England. 1880s-1890s 25 Inch First Edition Ordnance Survey mapping © Crown copyright and Landmark Information Group Ltd.

However disused medieval field boundaries were the single most frequently recorded monument type during the survey. They were visible either as earth banks or cropmarks that formed over the buried remains of a boundary bank or ditch, and a large number had ceased to function prior to the mid-19th century and were not depicted on the Tithe maps (e.g. MDV106517; MDV106520).

Some well-known prehistoric settlement sites were identified from cropmarks (e.g. MDV10254), as well as a few that are new to the Historic Environment Record (e.g. MDV105524). Abandoned medieval settlements were also visible as complex earthworks, including the newly recorded MDV106556 close to the better-known settlement of Dowlands MDV11401. The gradual levelling of the earthworks of the latter could be traced through the aerial photographs.

The second most frequently recorded type of monument is also of agricultural origin, but probably more recent than most of the field boundaries. Over 100 ‘catchmeadow’ systems, irrigating hill or valley sides using water channels from a pond or stream, were recorded and mostly interpreted as post-medieval or 19th century in date. All were new to the HER. Most were small in scale and take advantage of the steeply sloping combes leading to the coast, although some were very extensive (MDV104838).

Industry

Small scale extraction pits were very frequently recorded all along the coastal strip, particularly the chalk and flint pits in the east.

Quarrying at Berry Head Fort Number 3. RAF CPE/UK1890 3209 10-DEC-1946. Historic England (RAF Photography).
Quarrying at Berry Head Fort Number 3. RAF CPE/UK1890 3209 10-DEC-1946. Historic England (RAF Photography).

Several more extensive quarries were also recorded (e.g. MDV106101 and the large scale 20th century quarrying that impacted on the Napoleonic fort and prehistoric promontory fort at Berry Head in Torbay).

 

Quarrying at Berry Head Fort Number 3. NMR SX9456/39 RAF 30137/PSFO-P2-0034 27-AUG-1958.
Quarrying at Berry Head Fort Number 3. NMR SX9456/39 RAF 30137/PSFO-P2-0034 27-AUG-1958.
Possible saltern mounds at ‘Salt Plot’ on Seaton Marshes under snow cover in 1963 (MDV51123). The post-war part of the former Warner’s holiday camp is visible on the bottom right of the image (MDV53277). NMR RAF/58/5607 F21 343 22-JAN-1963. Historic England (RAF Photography).
Possible saltern mounds. NMR RAF/58/5607 F21 343 22-JAN-1963. Historic England (RAF Photography).

More unusually, the probable remains of the historic coastal industry of saltworking were recorded at Seaton. This had been documented in the 12th century and then from the early-18th century onwards, but had not previously been mapped.

Mounds bearing a resemblance to salterns found along the coast in other parts of England were visible at ‘Salt Plot’ on Seaton Marshes (MDV51123) on aerial photographs from the 1940s onwards, although not all have survived. Their form showed particularly well under light snow cover in winter 1963.

Maritime

From causeways to oyster racks, a variety of marine or estuarine features were visible on aerial photographs. Wrecks and hulks were the fourth most common type of monument recorded during the survey, including a large number of hulks in the Exe Estuary (e.g. MDV105599), but also the wreck of the Louis Sheid that ran aground off Thurlestone Sand in 1939 after being torpedoed by a German U-boat (MDV43504) and also possibly the medieval carvel-built ‘Axe boat’ (MDV105880).

The Wreck of the Louis Sheid three years after it was wrecked off Thurlestone Sand. SX 6742/4 MSO 31279/PO-3092 12-FEB-1942. Historic England (RAF Photography).
The Wreck of the Louis Sheid three years after it was wrecked off Thurlestone Sand. SX 6742/4 MSO 31279/PO-3092 12-FEB-1942. Historic England (RAF Photography).

Several previously unrecorded fish traps were also identified as post-built structures, perhaps obscured then exposed by the shifting estuarine muds and sands.

Possible fishtrap structures in the Erme Estuary in 2007; note the looped structure top right. NMP mapping © Historic England. The base map is © Crown Copyright and database right 2014. Ordnance Survey 100019783.
Possible fishtrap structures in the Erme Estuary in 2007; looped structure top right. NMP mapping © Historic England. The base map is © Crown Copyright and database right 2014. Ordnance Survey 100019783.

Most were visible only on the most recent aerial photographs, maybe suggesting a change in erosion or accretion processes.

One interesting ‘looped’ example (MDV104118) bears parallels to others along the coast of Brittany and within the Severn Estuary. Dating these is difficult but they may have a medieval origin.

Other unusual features specific to this location include the rock-cut rutways at Maer Rock, Exmouth (MDV105340), projecting into the intertidal zone for nearly 250 metres.

 

They have been interpreted as being contemporary with a limekiln, and were possibly cut into the exposed rock to facilitate the transportation of limestone or coal at low tide, when the use of carts over beach sand might have been difficult or dangerous. Interestingly, further tracks have been identified during the survey.

Your comments

Would you like to share additional information on any of the sites we recorded from aerial photographs, or do you have a different interpretation? Let us know! We read all submissions but unfortunately due to the volume of responses we are unable to respond personally to every comment.