Unlocking Our Coastal Heritage Project: Crane Castle Promontory Fort, Illogan, Cornwall

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1 Unlocking Our Coastal Heritage Project: Crane Castle Promontory Fort, Illogan, Cornwall As part of a wider project funded by the Rural Development Programme for England (RDPE) and administered through DEFRA, the South West Coast Path team (SWCP) and the National Trust (NT), a number of archaeological sites have been selected in order to better conserve, enhance and manage them. The sites were chosen on the basis that they were on or adjacent to the South West Coast Path and that they are currently at risk of being irreparably damaged or lost, or could be made more accessible for wider audiences. This strand of the project (Strand 1) is entitled Unlocking our coastal heritage protecting the cultural corridor. The site of Crane Castle comprises the remains of a prehistoric promontory fort in the form of substantial upstanding remains of a double rampart. Almost the entire interior area has been destroyed through the erosion of the cliff face. Pedestrian erosion over parts of its surface has also eroded elements of this scheduled monument. It was selected so that that loss of this finite resource should be mitigated by survey of the area and targeted evaluation of an eroding section (followed by consolidation) which would in turn provide a valuable amount of information for both engagement and future management. The overall scheme of works proposed comprises a geophysical survey of the surrounding area, a topographical survey of the scheduled monument and immediate area and evaluation of a small area of the scheduled monument focussed on the area impacted by human and coastal erosion. The topographical survey and excavation elements which are the subject of this brief will consist of the topographical survey of the wider area in order to illustrate and understand its position in the landscape, and evaluation of a small section across the earthworks which will enable a clearer understanding of the monument before it is lost to coastal erosion. Overall the work will enable safe future public access and use of the site, a clearer understanding of the archaeological resource and allow for informed management and conservation recommendations in relation to the threatened site to be made. Crane Castle is located on the edge of a prominent coastal cliff known as Carvannel Downs, overlooking Basset's Cove, some 2500m south west of the Portreath near Illogan (SW ). Much of the area of

2 the monument itself is short coastal grassland, the marginal areas however are covered in bracken, gorse, brambles etc.

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4 Archaeological Project Summary Crane Castle comprises the remains of a prehistoric promontory fort in the form of substantial upstanding remains of a double rampart. Almost the entire interior of the cliff castle has been destroyed through the erosion of the cliff face. Pedestrian erosion over areas of the upstanding ramparts has also eroded elements of this scheduled monument. Crane was selected for investigation so that the effects of the erosion could be measured against future loss. The overall scheme of archaeological works in comprised a geophysical survey of the surrounding area, a topographical survey of the scheduled monument and immediate area, and evaluation of a small area of the scheduled monument. The geophysical survey was undertaken by Archaeophysica with the remainder of the project being undertaken by Cornwall Historic Environment Service assisted by a group of very willing volunteers, including both experienced and inexperienced diggers. During the work participants were given training in the techniques of archaeological excavation and where time allowed, were given an introduction to site recording practices. The National Trust also organised a field trip by pupils from Illogan Primary School and Pool Academy, Camborne, who were given a talk on the excavations and helped excavate and sieve material from the spoil heap. An open day held on the last weekend of the evaluation gave passing walkers the chance to visit the excavated trench and learn about the project. The 2013 surveys and excavations represent the only systematic fieldwork carried out at the site and provided valuable information on the character and condition of the monument and the results are helping guide future management and wider interpretation. It is impossible to know exactly what the Crane Castle headland looked like prior to collapse into the sea. Crane Islands today certainly suggest that the tip was a rocky crag, probably some distance below the cliff. If it assumed that the cliff castle included what are now Crane Islands and that most of the cliff has been lost from the western side, this means the loss of approximately 5 hectares of land into the sea. The site has commanding views over the flat coastal plateau of Roskajeague Downs and North Cliffs and also out to sea, occupying a commanding position over Basset s Cove. The project has been a rare opportunity to investigate and record one of Cornwall s surviving cliff castles and successfully reveal the original ditch cuts and parts of rampart construction. Although dating evidence is limited to a single sherd of pottery, this is from an imported vessel

5 indicating contact with the wider world and provides a date for activity at Crane Castle in the early Romano-British period, circa 100 AD. The considerable depths of both ditches (1.5 to 2.5m) and their intact deposits were far greater than anticipated with their implications for investment and greater complexity at their time of construction. Clear potential for further archaeological work should be considered in the future. This evaluation has also confirmed condition and the state of preservation of the monument and emphasises the need for monitoring of coastal erosion on sites such as this. The project also provided a valuable opportunity to engage a volunteer team on a unique site and train them in the techniques of archaeological excavation and also made the work accessible to local schools and the general public. Interpretative material based on the results of the evaluation exercise will enable the National Trust to update their documentation relating to the prehistoric and later use of this stretch of the Cornish coast.

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