Two early post-medieval quays in north and north western Periglis, St Agnes


Heritage Category: Scheduled Monument

List Entry Number: 1016512

Date first listed: 02-Jul-1999


Ordnance survey map of Two early post-medieval quays in north and north western Periglis, St Agnes
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The building or site itself may lie within the boundary of more than one authority.

District: Isles of Scilly (Unitary Authority)

Parish: St. Agnes

National Grid Reference: SV8755408440, SV8757808498

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.

Quays are structures designed to enhance the natural landforms of coastal or riverside locations by providing sheltered landing places with sufficient depth of water alongside to accommodate vessels over part of the tidal cycle. The features and complexity of quays vary enormously depending partly on their date but also on their situation and exposure, the nature of the underlying geology and alluvium, and the volume and types of trade they need to handle. By their nature, quays also tend to occur in proximity to centres of trade and administrative authority. Usually in locations already sheltered to some extent by natural features, basic elements of quays may include platforms built up and out along a part of the coast or riverside that is naturally deep or artificially dredged, or along an artificial cut forming a small dock on a riverside or coast. Such features occur among the earliest surviving quays in England known from larger Roman urban centres, notably London, where they form the basis for an almost continuous development of quays to the present day. At least 26 quays are recorded on the Isles of Scilly, 12 of which remain in use. Of the disused quays, only that in Old Town Bay, St Mary's, is known to be of medieval date. Most of Scilly's disused post-medieval quays are associated with specific aspects of the islands' development and history, including examples serving the fuel supply to the lighthouse on St Agnes, the former quarantine station on St Helen's, and several built to load soda ash from the kelp burning industry. Quays display a considerable diversity of form, setting and construction. They comprise valuable sources of information on patterns of earlier trade, authority and settlement; their development shows clearly the relationship between economic forces and technological development in adapting the natural landscape to communities' needs. All medieval quays that are disused and survive substantially intact as upstanding monuments are nationally important. Disused post-medieval examples surviving substantially intact and forming distinctive indicators of pre-19th century trades and activities are also considered likely to be of national importance. The two early post-medieval quays in Periglis survive well, showing clearly their mode of construction which, in the case of the northern quay, included several phases employing differences in style and method. Their proximity to the island's main early settlement is typical and their rather difficult access across the bay from that settlement shows well the premium placed on siting quays where they can optimise shelter with relatively deep water navigable access. However the greatest significance of these quays derives from their early support role for the St Agnes Lighthouse; that lighthouse itself is a rare and little modified example of the early post-medieval coal-burning lighthouse towers, only the second to be built by Trinity House. These quays, as the major built element of the early infrastructure by which the lighthouse was maintained, are an integral part of the important group of surviving remains associated with that lighthouse.


The monument includes two early post-medieval quays, one known as `Uncle Tom's Quay', on the north and north west of Periglis, a small bay on the north west coast of St Agnes in the south west of the Isles of Scilly. The quays are in two areas of protection, and part of each extends below Mean Low Water level. Both quays project into the northern trough of the bay from an extensive raised spread of boulders that links the north of Periglis with Burnt Island, providing a measure of protection from severe westerly winds. The quay on the north west of the bay, called Uncle Tom's Quay, is a short rectangular structure 12.8m long, WSW-ENE, by up to 3.8m wide. It has a well-consolidated boulder and rubble core which is faced along both sides and across its ENE end by a roughly coursed wall of boulders laid end-on to the quay's face and often edge-down for increased stability. Any original upper surface of the quay has been disrupted by wave action. The WSW end of the quay merges with the natural boulder bank behind; as it extends ENE, the quay reaches a height of up to 1.5m from the rubble descending to the trough of the bay, reduced to 1.1m high by its ENE end by some loss of upper facing slabs. To the north east, the other surviving early quay projects into the north of the bay and shows multiple phases of construction and refurbishment. Its main arm extends over 30m south from the boulder bank behind the bay; its northern end merges into that bank as a broad ridge whose underlying structure is cloaked by recent wave-deposited rubble; as it rises from the shore to the south, its construction is revealed. It has a well-bedded boulder core with smaller rubble infilling gaps, faced on each side and the southern end by a wall of boulders mostly laid end-on to the wall face in rough courses. Part of the west facing has a possible original upper coping or later refurbishment course of smaller slabs than average, laid end-on and edge-down; no original surface is perceptible. This arm has a width of 3.5m, its facing rising to 1.5m on the east, 0.7m on the west, a difference due to the breakwater effect of the quay on deposition to each side. The main arm's facing extends to its southern end on both sides, but a westward extension was later added to this end, retaining the main arm's west facing across its base and giving the quay a reversed `L'-shaped plan. The extension is 6.5m long, 3.25m wide and up to 1.7m high, built in the same manner as the main arm but with its facing employing a more regular choice of smaller elongated slabs. From the end of this extension, an artificial but poorly consolidated boulder bank extends WNW, finally petering out after 15m; the bank is up to 3.5m wide and 1m high on the east where its southern edge is revetted over several metres by a line of large upright slabs to 0.9m high. This remnant of slab-revetted bank may be a survival of an earlier quay structure on this site, otherwise destroyed by the more substantially-built main arm and its extension. The bay of Periglis containing these two long-abandoned quays was formerly St Agnes's principle mooring and landing place, serving the island's main medieval and post-medieval settlement around the parish church at the south east of the bay. Although all of the larger inhabited islands on Scilly were furnished with quays and jetties by the 19th century, the main stimulus for the construction and maintenance of the unusually large early quays in this scheduling was the need to offload the coal to fuel the light at the St Agnes lighthouse from its construction in 1680 until its conversion to oil-burning lamps in 1790. An account of 1750 records that the coal was supplied annually by ship, and in 1764 one of the colliers carrying fuel for the lighthouse was totally wrecked off Burnt Island, which provides a hazard as well as shelter at the western entrance to Periglis. When the bay was first subject to detailed mapping by the Ordnance Survey in 1888, the northern quay in the bay was shown as the western of two near-parallel quays depicted as amorphous banks in like manner to the adoining boulder spread, implying they were already not being maintained by that date; no surviving trace is now perceptible of the eastern of these quays. The north western `Uncle Tom's Quay' was shown in hard outline in 1888 and it may still have retained some role at that date.

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: 15529

Legacy System: RSM


Books and journals
Aldridge, W, Hobnails and Seaboots, (1956)
Gill, C, The Isles of Scilly, (1975)
Gill, C, The Isles of Scilly, (1975)
Heath, R, A Natural and Historical Account of the Isles of Scilly, (1750)
Larn, R, Shipwrecks of the Isles of Scilly, (1993)
Title: 1:10000 Ordnance Survey Map, SV 80 NE Source Date: 1980 Author: Publisher: Surveyor:
Title: 1:2500 Ordnance Survey Map, Cornwall sheet LXXXVII:14 Source Date: 1888 Author: Publisher: Surveyor:
Title: 1:2500 Ordnance Survey Map; Cornwall sheet LXXXII: 10 Source Date: 1888 Author: Publisher: Surveyor:
Title: 1:2500 Ordnance Survey Map; Cornwall sheet LXXXVII: 14 Source Date: 1906 Author: Publisher: Surveyor:
Title: 1:2500 Ordnance Survey Map; SV 8708 Source Date: 1980 Author: Publisher: Surveyor:
Title: 1:2500 Ordnance Survey Map; SV 8808 Source Date: 1980 Author: Publisher: Surveyor:
Waters, A/CAU, AM 107 for Scilly SMR entry PRN 7006, (1988)
Waters, A/CAU, Scilly SMR entry PRN 7006, (1988)

End of official listing