Prehistoric cairn group on Abbey Hill, Tresco

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. Round cairns are funerary monuments of Bronze Age date (c.2000-700 BC). They were constructed as mounds of earth and stone rubble, up to 40m in external diameter, though usually considerably smaller, covering single or multiple burials. A kerb of edge-set stones sometimes bounds the edge of the mound. Burials were placed in small pits, or on occasion within a box-like structure of stone slabs called a cist, set into the old ground surface or dug into the body of the cairn. Round cairns can occur as isolated monuments, in small groups or in larger cemeteries. Round cairns form a high proportion of the 387 surviving cairns recorded on the Isles of Scilly. Their considerable variation in form and longevity as a monument type provides important information on the diversity of beliefs, burial practices and social organisation in the Bronze Age and a substantial proportion of surviving examples are considered worthy of preservation.

The linear cairn group on Abbey Hill survives well and shows little evidence for disturbance; the later structures at the summit cairn have had no substantial effect on the fabric of the cairn's mound while the surviving evidence for that cairn's kerb illustrates the diversity of structural features that such cairns may display. The cairn group's linear arrangement along the crest of this prominent ridge shows well the influence of natural landforms in the expression of prehistoric funerary and ritual activity. The broadly contemporary context of the cairn group is demonstrated by the surviving prehistoric field systems and settlement sites on the shores of the west coast of Tresco, giving an insight into the organisation of prehistoric land use across an unusually broad altitude range prior to the islands' extensive submergence.

Details

The scheduling includes a linear group of four prehistoric round cairns, in two areas of protection, extending along the western ridge of Abbey Hill, overlooking the west coast of southern Tresco in the Isles of Scilly. The scheduling also includes remains of a post-medieval watch house at the base of a late-19th century memorial obelisk built onto the cairn occupying the summit of the ridge. The cairn group extends in a straight line over 85m of the hill's western ridge. A gap of 25m separates the northern two cairns from the southern two; the cairns in the northern pair are spaced 10m apart and those in the southern pair are 9m apart. Each cairn is visible as a shallow-domed rounded or ovoid mound of turf-covered earth and rubble. In the northern pair, the northern cairn measures 12m in diameter and rises to 0.8m high; the southern cairn is 9m in diameter and rises to 0.6m high. In the southern pair, the northern cairn is situated on the summit of the ridge and measures 15m east-west, 14m north-south and rises up to 1m high, while the cairn to its south is 9m north-south by 7m east-west and rises to 0.7m high. Only the cairn on the summit has visible evidence for further prehistoric elaboration. The top of this cairn's mound has been modified by construction of the watch house and the later memorial obelisk, but beyond the base of the memorial a line of large rough slabs, up to 1.2m long by 0.8m wide and 0.1m high, forms a low kerb embedded in the fabric of the mound on a curve c.8m in diameter, visible around the north and north west, and intermittently on the west and south west. The kerb defines the perimeter of a flattened platform which contains the much later features. The earliest post medieval structural activity affecting the summit cairn is the watch house whose ruins were recorded on top of Abbey Hill by the Revd John Troutbeck in 1796; its remains will have been largely removed and reused for the building of the late 19th century memorial obelisk but its former presence is considered to account for a flat rectangular slab, 0.8m long by 0.4m wide, embedded in the mound's upper surface close to the southern foot of the obelisk but forming no part of the memorial itself. The late-19th century memorial was erected on top of the cairn in memory of Augustus Smith, the lessee of the Isles of Scilly and the major formative influence on the islands' modern economy from 1834 until his death in 1872. It was designed shortly before his death by Augustus Smith himself and consists of a squat obelisk built of large coursed granite slabs with deliberately rough and highly irregular outer faces. Adjoining the eastern foot of the obelisk is a small railed garden bed whose low edging slabs extend to the eastern crest of the mound's upper platform. Beyond this scheduling, remains of broadly contemporary field systems and settlement sites survive in now-submerged locations on the western shores of Tresco, to both the north west and south of this cairn group. The late-19th century memorial obelisk, which is Listed Grade II, the modern seat and railings are excluded from the scheduling, although the ground beneath these features is included.

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:

15506

Legacy System:

RSM

Sources

Books and journals
Inglis-Jones, E, Augustus Smith of Scilly, (1969)
Inglis-Jones, E, Augustus Smith of Scilly, (1969)

Other
Title: 1:2500 Ordnance Survey Map; SV 8914 Source Date: 1980 Author: Publisher: Surveyor:
Title: 1:2500 Ordnance Survey Map; Cornwall sheet LXXXVII: 2 Source Date: 1908 Author: Publisher: Surveyor:
Title: 1:2500 Ordnance Survey Map; Cornwall sheet LXXXVII: 2 Source Date: 1888 Author: Publisher: Surveyor:
Isles of Scilly; 1358 - 0/7/118, DNH, List of Buildings of Special Architectural or Historic Interest, (1992)
Parkes, C/CAU, AM 107 for Scilly SMR entry PRN 7322.02, (1988)
Parkes, C/CAU, AM 107 for Scilly SMR entry PRN 7322.01, (1988)
Parkes, C/CAU, AM 107 for Scilly SMR entry PRN 7321.02, (1988)
Parkes, C/CAU, AM 107 for Scilly SMR entry PRN 7321.01, (1988)
Parkes, C/CAU, AM 107 for Scilly SMR entry PRN 7320, (1988)

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