Two kerbed platform cairns 240m north of the Pest House, St Helen'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.

These platform cairns on St Helen's have survived well and have not been excavated. Their location relative to other broadly contemporary funerary and settlement monuments on this island shows well the wider organisation of prehistoric land use.

Details

The monument includes two prehistoric kerbed platform cairns situated on the upper western slope of a spur that extends NNW from the summit of St Helen's, an uninhabited island in the north of the Isles of Scilly. The platform cairns are situated 23.5m apart on a north west-south east axis. The south eastern cairn survives with a heather-covered circular mound of heaped rubble 6.5m in diameter, rising 0.2m to a flattened platform 4.5m in diameter. Two small edge-set slabs are visible from a perimeter kerb; the largest slab, on the ENE, is 0.7m long and 0.25m high; the smaller slab, on the south west, is 0.3m long and 0.2m high. The north western cairn is visible as a platform 4.7m in diameter, levelled into the slight westerly slope, without surface traces of a rubble core. The platform's perimeter is defined by a kerb of at least seven closely-spaced slabs, up to 1.25m long and 0.25m high, mostly edge-set but including one large slab displaced inwards and lying flat on the platform's eastern sector. The kerb extends around most of the platform, only leaving a substantial gap at the south. Within 150m of these cairns, other broadly contemporary monuments on St Helen's include a further two kerbed platform cairns located near the northern end of the same spur and a large round cairn containing a funerary cist situated on the island's summit. Prehistoric field systems also occur on the island's lower western slopes and on the higher slope east of the summit. These features are the subjects of separate schedulings.

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:

15431

Legacy System:

RSM

Sources

Other
Title: 1:10000 Ordnance Survey Maps: SV 81 NE & SV 91 NW Source Date: 1980 Author: Publisher: Surveyor:
Title: 1:10000 Ordnance Survey Maps: SV 81 NE & SV 91 NW Source Date: 1980 Author: Publisher: Surveyor:
consulted 1995, Parkes, C/CAU, AM 107 for Scilly SMR entry PRN 7114, (1988)
consulted 1995, Parkes, C/CAU, AM 107s for Scilly SMR entries PRN 7267.03 & .04, (1988)
consulted 1995, Parkes, C/CAU, AM 107 for Scilly SMR entry PRN 7267.02, (1988)
consulted 1995, Parkes, C/CAU, AM 107s for Scilly SMR entries PRN 7267.03 - .04, (1988)
consulted 1995, Parkes, C/CAU, AM 107s for Scilly SMR entries PRN 7112-3, (1988)

End of official list entry

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