Kerbed platform cairn 90m north west of Old Rock, Porth Hellick Down, St Mary's

Reasons for Designation

The Isles of Scilly, the westernmost of the granite masses of south west England, contain a remarkable abundance and variety of archaeological remains from over 4000 years of human activity. The remote physical setting of the islands, over 40km beyond the mainland in the approaches to the English Channel, has lent a distinctive character to those remains, producing many unusual features important for our broader understanding of the social development of early communities. Throughout the human occupation there has been a gradual submergence of the islands' land area, providing a stimulus to change in the environment and its exploitation. This process has produced evidence for responses to such change against an independent time-scale, promoting integrated studies of archaeological, environmental and linguistic aspects of the islands' settlement. The islands' archaeological remains demonstrate clearly the gradually expanding size and range of contacts of their communities. By the post- medieval period (from AD 1540), the islands occupied a nationally strategic location, resulting in an important concentration of defensive works reflecting the development of fortification methods and technology from the mid 16th to the 20th centuries. An important and unusual range of post- medieval monuments also reflects the islands' position as a formidable hazard for the nation's shipping in the western approaches. The exceptional preservation of the archaeological remains on the islands has long been recognised, producing an unusually full and detailed body of documentation, including several recent surveys. Platform cairns are funerary monuments of Early Bronze Age date (c.2000-1600 BC). They were constructed as low flat-topped mounds of stone rubble, up to 40m in external diameter though usually considerably smaller, covering single or multiple burials. Some examples have other features, including peripheral banks and internal mounds constructed on the platform. A kerb of slabs or edge-set stones sometimes bounds the edge of the platform, and a peripheral bank or mound if present. Platform cairns can occur as isolated monuments, in small groups or in cairn cemeteries. In cemeteries they are normally found alongside cairns of other types. Platform cairns form a significant proportion of the 387 surviving cairns on the Isles of Scilly; this is unusual in comparison with the mainland. All surviving examples on the Isles of Scilly are considered worthy of protection.

This platform cairn on Porth Hellick Down has survived well and has not been excavated. The presence of this monument within a cemetery containing various cairn types, its proximity to a prehistoric field system on the western slope of the Down, and the disposition of this and the other cairn cemeteries on successive downs along the coast are all factors combining to illustrate well the diversity of funerary practices and the organisation of land use during the Bronze Age.

Details

The monument includes a prehistoric platform cairn situated on the southern part of Porth Hellick Down, on south eastern St Mary's in the Isles of Scilly. The platform cairn survives with a circular mound of heaped rubble, 7.5m in diameter and 0.4m high. The mound rises to a flattened platform, 4m in diameter, sloping in conformity with the surrounding slight southerly hillslope. Two small, spaced, edge-set kerb stones, up to 0.5m wide and 0.3m high, are visible on the northern edge of the platform. This monument forms part of a cairn cemetery containing at least eight other cairns dispersed across the central plateau of Porth Hellick Down. The cairns in this cemetery vary in form but include at least six entrance graves, forming one of the largest surviving groupings of this type of monument. A broadly contemporary field system extends along the north west slope of the Down. Other prehistoric cairn cemeteries are located on the adjacent coastal downs of Salakee Down to the south west and Normandy Down to the NNE.

MAP EXTRACT The site of the monument is shown on the attached map extract. It includes a 2 metre boundary around the archaeological features, considered to be essential for the monument's support and preservation.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

15363

Legacy System:

RSM

Sources

Books and journals
Russell, V, Isles of Scilly Survey, (1980)
Ashbee, P, Ancient Scilly, (1974)

Other
Title: 1:2500 Ordnance Survey Map; SV 9210 Source Date: 1980 Author: Publisher: Surveyor:
consulted 1994, Waters, A., AM 107 for Scilly SMR entry PRN 7527, (1988)
consulted 1994, Waters, A., AM 107 for Scilly SMR entry PRN 7528.06, (1988)
consulted 1994, Waters, A., AM 107 for Scilly SMR entry PRN 7528, (1988)

End of official list entry

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