Entrance grave 105m south east of Basin Rock, Porth Hellick, 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. Entrance graves are funerary and ritual monuments whose construction and use dates to the later Neolithic, Early and Middle Bronze Age (c.2500-1000 BC). They were constructed with a roughly circular mound of heaped rubble and earth, up to 25m in diameter, whose perimeter may be defined by a kerb of edge-set slabs or, occasionally, coursed stone. The mound contains a rectangular chamber built of edge-set slabs or coursed rubble walling, or a combination of both. The chamber was roofed by further slabs, called capstones, set across the chamber. The chamber was accessible via a gap in the mound's kerb or outer edge and often extends back beyond the centre of the mound. The cairn's mound and chamber may incorporate natural boulders and outcrops. Excavations in entrance graves have revealed cremated human bone and funerary urns, usually within the chambers but on occasion within the mound. Unburnt human bone has also been recovered but is only rarely preserved. Some chambers have also produced ritual deposits of domestic midden debris, including dark earth typical of the surface soil found within settlements, animal bone and artefact fragments. Entrance graves may occur as single monuments or in small or large groups, often being associated with other cairn types in cemeteries. They may also occur in close proximity to broadly contemporary field boundaries. The national distribution of entrance graves is heavily weighted towards the Isles of Scilly which contain 79 of the 93 surviving examples recorded nationally, the remaining 14 being located in western Cornwall.



This entrance grave on Porth Hellick Down has survived well, retaining clearly its original form and construction despite the loss of its northern capstones. The incorporation of natural outcrops into the cairn is a feature found in certain other cairns on the Isles of Scilly but unusual and rare nationally. 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 entrance grave, also known as Peter's Barrow, situated near the centre of Porth Hellick Down, on south eastern St Mary's in the Isles of Scilly.

The entrance grave survives with a circular mound of heaped rubble, 10m in diameter and 1m high, incorporating two natural outcrops, up to 2.3m long, 1.5m wide and 1.5m high. One outcrop is located on the SSW perimeter of the cairn, the other is south east of the mound's centre. Smaller flat outcrops are located beside the north east perimeter of the mound.

The mound rises to at least four turf-level slabs of a low kerb, which includes the south eastern outcrop in its line, defining a circular flattened platform, 5.5m in diameter. Almost bisecting the platform is a funerary chamber with its long axis orientated north-south, the entrance facing north and its south east corner abutting the mound's south eastern outcrop. The chamber interior measures 4m north-south by up to 1m wide, its northernmost 1.75m at the entrance being narrowed to 0.6m wide. The chamber is lined by edge-set slabs, with coursed slabs at the southern end of the east side, and a terminal slab across the southern end. Two large slabs, called capstones, up to 1.8m long, 0.9m wide and 0.4m thick, span the southern half of the chamber's roof giving an internal height of 0.6m. Capstones formerly covering the northern half are missing due to relatively recent stone-robbing.

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 at least six of these are 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, including entrance graves, 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:

15365

Legacy System:

RSM

Sources

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

Other
Title: 1:2500 Ordnance Survey Map; SV 9210 Source Date: 1980 Author: Publisher: Surveyor:
Rees, S., AM7 scheduling documentation for CO 1026, 1975, consulted 1994
consulted 1994, Waters, A., AM 107 for Scilly SMR entry PRN 7527, (1988)
consulted 1994, Waters, A., AM 107 for Scilly SMR entry PRN 7528.05, (1988)
consulted 1994, Waters, A., AM 107 for Scilly SMR entry PRN 7528, (1988)

End of official list entry

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