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The Giant's Castle cliff castle, St Mary's

A Scheduled Monument in St. Mary's, Isles of Scilly

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Latitude: 49.9117 / 49°54'41"N

Longitude: -6.2852 / 6°17'6"W

OS Eastings: 92461.980386

OS Northings: 10079.056157

OS Grid: SV924100

Mapcode National: GBR BXVX.KVS

Mapcode Global: VGYC5.0HL2

Entry Name: The Giant's Castle cliff castle, St Mary's

Scheduled Date: 7 October 1976

Last Amended: 16 March 1995

Source: Historic England

Source ID: 1011935

English Heritage Legacy ID: 15354

County: Isles of Scilly

Civil Parish: St. Mary's

Built-Up Area: St Mary's Airport

Traditional County: Cornwall

Lieutenancy Area (Ceremonial County): Cornwall

Church of England Parish: Isles of Scilly

Church of England Diocese: Truro


The monument includes an Iron Age cliff castle, called the Giant's Castle,
situated on a small rocky promontory on the southern edge of Salakee Down, on
the southern coast of St Mary's in the Isles of Scilly. The monument also
includes remains of a Second World War firing target built into the outermost
rampart of the cliff castle.
The cliff castle occupies a steep-sided promontory, 0.4ha in extent, rising
10m in height to natural outcrops on the summit from the foot of the Down to
the north. The east and south west sides of the promontory and its southern
tip are defined by near vertical sea cliffs, 15m-25m high, forming natural
defences for the cliff castle.
The cliff castle has a small irregular internal area measuring 25m east-west
by 20m north-south, occupying the restricted area of almost level ground north
and east of the promontory's summit outcrops. The internal area is defined to
the south and south west by the cliffs of the promontory's southern tip. The
north and north east sides of the internal area are defined by the innermost
of the cliff castle's defensive series of four concentric ramparts accompanied
by outer ditches.
The ramparts and ditches occupy almost the entire steep northern slope of the
promontory from the crest of its summit to the floor of the broad saddle
linking the promontory with the foot of Salakee Down. The ramparts are visible
as earth-and-rubble banks, frequently incorporating large natural boulders and
outcrops, and surviving up to 4.5m wide, running 8m to 12m apart along the
contour of the slope. The ramparts are truncated at both ends by the erosion
surfaces and outcrops beside the east and south west cliff faces of the
promontory, except where the World War II firing target, described below,
has been built into the western end of the outer rampart. The inner two
ramparts, uppermost on the promontory, are markedly asymmetrical in profile,
forming scarps up to 2.5m high on the outer side, with upper surfaces running
back to the slope, either level or rising in places to 0.1m high along their
inner sides. The outer, lower, two ramparts are up to 1m high on their outer
sides and 0.3m high on their inner sides. Ditches survive up to 2.5m wide and
0.2m deep along parts of the outer edges of the ramparts, the remaining
lengths of ditch being infilled by silt and rubble washed down the slope. Two
slight cross-banks are also present, running directly downslope and together
forming a staggered line linking the inner three of the concentric ramparts in
their western sectors.
In addition to the surviving visible evidence of the cliff castle, fragments
of Iron Age pottery were recovered from a cutting made by the army on the
outer edge of the cliff castle during World War II.
Also during World War II, a practice-firing target for military aircraft was
built into the western end of the outermost rampart. The target is formed as
an unroofed rectangular building, surviving with a turf-covered earthen bank,
from 1m to 3m wide and up to 1m high, faced on its inner side by a tumbling
wall face of rough, uncoursed rubble and slabs. This inner facing defines a
rectangular internal area measuring 5m north east-south west by 2m wide, open
at the south west end. A slight hollow, 1m wide, located near the north east
end of the south east bank, marks the entrance to the target's internal area.
Beyond this monument, over a dozen surviving funerary cairns of Bronze Age
date are arranged as dispersed groups on Salakee Down from 150m to the west.

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.

Source: Historic England

Reasons for Scheduling

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'
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.

Cliff castles are coastal promontories adapted as enclosures and fortified on
the landward side by the construction of one or more ramparts accompanied by
ditches. On the seaward side, the precipitous cliffs of the promontory
provided a natural defence, only rarely reinforced by surviving artificial
ditches. They date to the Iron Age, most being constructed and used between
the 2nd century BC and the 1st century AD. Cliff castles are usually
interpreted as high status defensive enclosures, related to the broadly
contemporary classes of hillforts. Despite their coastal situation, many cliff
castles occupy locations offering little scope for withstanding siege or
conducting trade. These monuments relate rather to a series of monument
classes in which high status was conferred on their occupants, or those with
access to them, by the enclosure of visually dramatic elements in the
landscape, in this case conspicuous rocky headlands.
The inner area enclosed at cliff castles varies with the size and shape of the
promontory, generally in the range from 0.5 to 3 ha, but occasional much
larger examples are known, enclosing up to 52 ha. The area of many cliff
castles will have been reduced by subsequent coastal erosion. The ramparts are
of earth and rubble, occasionally with a drystone revetment wall along their
outer face. Ditches may be rock- or earth-cut depending on the depth of the
subsoil. The number and arrangement of ramparts and ditches varies
considerably and may include outworks enclosing large areas beyond the
promontory and annexes defining discrete enclosures against the landward side
of the defences. Multiple ramparts may be close-spaced or may include a broad
gap between concentric ramparts defining inner and outer enclosures. Entrance
gaps through the defences are usually single, and often staggered where they
pass through multiple ramparts.
Internal features, where visible, include circular or subrectangular levelled
platforms for stone or timber houses, generally behind the inner bank or
sheltered by the promontory hill. Where excavated, cliff castles have produced
post and stakeholes, hearths, pits and gullies associated with the house
platforms, together with spreads of occupation debris including, as evidence
for trade and industrial activity, imported pottery and iron-working slag.
Cliff castles are largely distributed along the more indented coastline of
western Britain; in England they are restricted to the coasts of north Devon,
Cornwall and the Isles of Scilly. Sixty cliff castles are recorded nationally,
of which around 40 are located on the coasts of Cornwall.
The three cliff castles recorded on the Isles of Scilly form the western limit
of the national distribution and each shows a markedly different layout from
the other two, emphasising the diversity of this class of monument even within
such a geographically restricted area.
Cliff castles are of great importance in our understanding of how society and
the landscape was organised during the Iron Age, especially in providing clear
evidence for the influence of landscape features on the chosen locations for
prestigious settlement, trade and industry. All cliff castles where coastal
erosion does not pose a short-term threat to the preservation of substantial
remains will be considered worthy of preservation.
The Giant's Castle cliff castle has survived well. The World War II firing
target and army cutting have caused only minor disruption to the outer rampart
and ditch, while the cutting provided pottery evidence confirming the date of
the monument. The rest of the monument's defensive system and interior remain
unaffected and have not been excavated, surviving as a good example of a cliff
castle with multiple, close-spaced ramparts. In conjunction with the two other
differing cliff castles on the Isles of Scilly, the Giant's Castle shows well
the diversity of this class of monument. The proximity of this monument to the
earlier, Bronze Age, funerary cairns on Salakee Down illustrates the
development of land use on this coastal margin during the later prehistoric

Source: Historic England


Books and journals
Ashbee, P, Ancient Scilly, (1974)
O'Neil, BH St J, Ancient Monuments of the Isles of Scilly, (1960)
Ratcliffe, J, Scilly's Archaeological Heritage, (1992)
Ratcliffe, J, The Archaeology of Scilly, (1989)
Ashbee, P, 'Cornish Archaeology' in Ancient Scilly: retrospect, aspect and prospect, , Vol. 25, (1986), 186-219
Sharpe, A, 'Cornish Archaeology' in Treryn Dinas: Cliff Castles Reconsidered, , Vol. 31, (1992), 65-8
17/1/1994, Information given by Jeanette Ratcliffe to MPP fieldworker, (1994)
17/1/94, Information given to MPP fieldworker by Jeanette Ratcliffe, CAU, (1994)
consulted 1994, CAU, AM 107s for Scilly SMR entries PRN 7531; 7534; 7537; 7539; 7540, (1988)
consulted 1994, Waters, A., AM 107 for Scilly SMR entry PRN 7536, (1988)
Mr Humphrey Wakefield, Newman House,St Mary's, Information told to MPP fieldworker, (1994)
Mr Humphrey Wakefield, Newman House,St Mary's, Information told to the MPP fieldworker, (1994)
Mrs Penny Rogers, Lunnon Farm, St Mary's, Information told to MPP fieldworker, (1994)
Mrs Penny Rogers, Lunnon Farm, St Mary's, Information told to the MPP fieldworker, (1994)
Rees, S., AM7 scheduling documentation for CO 1023, 1975,
Title: 1:2500 Ordnance Survey Map; SV 9210
Source Date: 1980

Title: 6": 1 mile Ordnance Survey Map equivalent to SV 91 SW
Source Date: 1963

Source: Historic England

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