Kerbed platform cairn 125m north east of Holmbush Carn, Great Ganilly

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 kerbed platform cairn on Great Ganilly has survived well and has not been excavated. The relationships between this monument, the other varied types of funerary cairn and field system on the Eastern Isles, and the known submergence of the land since they were built, illustrate in a dramatic way the major environmental changes that have affected the setting of some surviving prehistoric monuments since their construction. They also show the diversity of funerary practices and the organisation of land use among prehistoric communities.

Details

The monument includes a prehistoric kerbed platform cairn with central funerary cist situated on the north crest of the northern hill of Great Ganilly, the largest of the Eastern Isles in the Isles of Scilly. This is the north eastern of two kerbed cairns on this hill.

The platform cairn survives with an ovoid mound of heaped rubble measuring 8.5m east west by 7m north-south overall. The mound is built out from the crest of the slope to the north west, up to 1m high on that side but only 0.3m high from the south, rising to the outer rim of a slightly depressed central platform, measuring 4m east-west by 3.5m north south and generally 0.2m below the level of the rim. Parts of two slab-built kerbs are visible. The outer kerb includes occasional, well-spaced large slabs on the east, south west and north west perimeter of the mound, the largest, 1.9m long, lying along the north western edge. The inner kerb extends around the southern outer rim of the central platform and includes a row of almost contiguous slabs, up to 1m long and 0.5m high, at least two of which are edge-set. At the centre of the platform is a flat slab whose exposed area measures 1m north west-south east by 0.6m north east-south west, set flush with the platform surface. From the size, setting and location of the slab, it is considered to be the covering stone of a slab-built, box-like funerary structure called a cist.

Although this cairn is located on what is now a fairly small uninhabited island, the physical environment in which it was originally built was a rocky ridge towards the eastern edge of the single large island that formerly united much of the area of the present Isles of Scilly archipelago, from St Mary's northwards. The gradual sinking of the land since this cairn was constructed has led to the fragmentation of that island into the present scatter of large and small islands and rocks. Broadly contemporary funerary cairns and field systems of various types are located on other islands in the Eastern Isles group, all formerly hills on the eastern margin of the pre- submergence island.

Near this kerbed cairn, on the same northern hill of Great Ganilly, these other monuments include another kerbed cairn 65m to the south west and a prehistoric field system from 90m to the south.

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:

15388

Legacy System:

RSM

Sources

Books and journals
Thomas, C, Exploration of a Drowned Landscape, (1985)
Thomas, C, Exploration of a Drowned Landscape, (1985)
Russell, V, Isles of Scilly Survey, (1980)

Other
Title: 1:10000 Ordnance Survey Map; SV 91 SW Source Date: 1980 Author: Publisher: Surveyor:
Rees, S., AM7 scheduling documentation for CO 1027, 1975, Cairn 'b'. Consulted 1994
consulted 1994, Ratcliffe, J., AM 107 for Scilly SMR entry PRN 7211, (1988)
consulted 1994, Ratcliffe, J., AM 107 for Scilly SMR entry PRN 7210.03, (1988)
consulted 1994, Ratcliffe, J., AM 107 for Scilly SMR entry PRN 7210.01, (1988)
consulted 1994, Ratcliffe, J., AM 107 for Scilly SMR entry PRN 7210, (1988)

End of official list entry

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