Prehistoric linear boundary SSE of The Island, Bryher


Heritage Category: Scheduled Monument

List Entry Number: 1014991

Date first listed: 04-Oct-1996


Ordnance survey map of Prehistoric linear boundary SSE of The Island, Bryher
© Crown Copyright and database right 2019. All rights reserved. Ordnance Survey Licence number 100024900.
© British Crown and SeaZone Solutions Limited 2019. All rights reserved. Licence number 102006.006.
Use of this data is subject to Terms and Conditions.

The above map is for quick reference purposes only and may not be to scale. For a copy of the full scale map, please see the attached PDF - 1014991 .pdf

The PDF will be generated from our live systems and may take a few minutes to download depending on how busy our servers are. We apologise for this delay.

This copy shows the entry on 21-Jan-2019 at 17:39:08.


The building or site itself may lie within the boundary of more than one authority.

District: Isles of Scilly (Unitary Authority)

Parish: Bryher

National Grid Reference: SV 88128 14815


Legacy Record - This information may be included in the List Entry Details.

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. The early linear boundaries on the Isles of Scilly were constructed from the Bronze Age to the early medieval period (c.2000 BC-AD 1066): closer dating within that period may be provided by their visible relationships to other classes of monument, or by their relationship with an earlier recorded sea level. They consist of stone walls, up to 3m wide and 1.1m high but usually much slighter, and are formed of heaped rubble, often incorporating edge- or end-set slabs called orthostats. Linear boundaries served a variety of functions. These included separating land regularly cultivated from that less intensively used, separating land held by different social groups, or delineating areas set aside for ceremonial, religious and funerary activities. Linear boundaries are often associated with other forms of contemporary field system. The Isles of Scilly contain examples of an associaton, rarely encountered elswhere, whereby certain linear boundaries directly link several cairns, entrance graves and cists in some groups of prehistoric funerary monuments. Linear boundaries along the coastal margin of the islands are often indistinguishable from the truncated upper walls of early field systems whose remaining extent has been destroyed by the rising sea level. Linear boundaries form a substantial part of the evidence of early field systems recorded on the Isles of Scilly. They provide significant insights into the physical and social organisation of past landscapes and form an important element in the existing landscape. Even where truncated by the rising sea level, their surviving lengths provide important evidence for the wider contemporary context within which other nationally important monuments at higher altitudes were constructed. A substantial proportion of surviving examples are considered worthy of protection.

This boundary SSE of The Island survives well, clearly displaying its mode of construction and forming a substantial exposure of a more extensive linear boundary whose course remains masked beneath later deposits. Its survival within the inter-tidal zone, despite rising sea levels, confirms its long term stability against a considerable period of submergence. The proximity of this boundary to the other inter-tidal field system and settlement remains in Green Bay and the east coast of Samson Hill, and to the cairn cemetery on the summit of Samson Hill, demonstrates the relationship between domestic, farming and funerary activities among the prehistoric communities that used this monument. It also complements those nearby prehistoric field system and settlement survivals at various levels around southern Bryher in providing an unusually complete view of prehistoric land use across the altitude range into the now-submerged zone.


Legacy Record - This information may be included in the List Entry Details.


The monument includes a prehistoric linear boundary exposed in the inter-tidal zone SSE of a small headland called The Island at the northern end of Green Bay on eastern Bryher in the Isles of Scilly. The linear boundary survives as a wall of closely spaced, often continuous, row of boulders and slabs, generally 0.6m long, 0.5m wide and 0.5m high; many of the slabs are edge-set, their faces in line with the wall's alignment. The boundary is visible over 28m on a slightly curving course, initially heading SSE from its northern end then tending towards the south. The continuation of the boundary beyond this scheduling is masked from both ends by the later sands and silts deposited on the middle shore. This linear boundary forms the northern known exposure of an extensive area of prehistoric land division in the now-submerged zone of Green Bay. Other exposures beyond this scheduling include a field system, enclosure, trackway and settlement sites in the central and southern parts of the bay, from 200m to the south west of this scheduling, which are separated by areas whose prehistoric land surface is now largely masked by the shore sand and shingle overburden. Another broadly contemporary linear boundary and settlement site is located in the small bay to the north of The Island, from 240m north of this scheduling. The summit of Samson Hill, overlooking this scheduling from the south, contains a prehistoric cairn cemetery, while the inter-tidal remains which include this scheduling in Green Bay are complemented on the south west coast of Bryher by another prehistoric field system and settlement surviving in Great Porth and extending over the Heathy Hill promontory; these prehistoric 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.


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

Legacy System number: 15466

Legacy System: RSM


Parkes, C/CAU, AM 107 for Scilly SMR entry PRN 7374, (1988)
Parkes, C/CAU, AM 107 for Scilly SMR entry PRN 7386, (1988)
Parkes, C/CAU, AM 107s for Scilly SMR entries PRN 7305, 7306, 7386, (1988)
Title: 1:2500 Ordnance Survey Maps; SV 8714 & 8814 Source Date: 1980 Author: Publisher: Surveyor:

End of official listing