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.
Platform cairns are funerary monuments of Early Bronze Age date (c.2000-1600
BC). They were constructed as low flat-topped mounds of stone rubble, up to
40m in external diameter though usually considerably smaller, covering single
or multiple burials. Some examples have other features, including peripheral
banks and internal mounds constructed on the platform. A kerb of slabs or
edge-set stones sometimes bounds the edge of the platform, and a peripheral
bank or mound if present. Platform cairns can occur as isolated monuments, in
small groups or in cairn cemeteries. In cemeteries they are normally found
alongside cairns of other types.
Platform cairns form a significant proportion of the 387 surviving cairns on
the Isles of Scilly; this is unusual in comparison with the mainland. All
surviving examples on the Isles of Scilly are considered worthy of protection.
These platform cairns on St Helen's have survived well and have not been
excavated. Their location relative to other broadly contemporary funerary and
settlement monuments on this island shows well the wider organisation of
prehistoric land use.
Details
The monument includes two prehistoric kerbed platform cairns situated on the
upper western slope of a spur that extends NNW from the summit of St Helen's,
an uninhabited island in the north of the Isles of Scilly. The platform cairns
are situated 23.5m apart on a north west-south east axis.
The south eastern cairn survives with a heather-covered circular mound of
heaped rubble 6.5m in diameter, rising 0.2m to a flattened platform 4.5m in
diameter. Two small edge-set slabs are visible from a perimeter kerb; the
largest slab, on the ENE, is 0.7m long and 0.25m high; the smaller slab, on
the south west, is 0.3m long and 0.2m high.
The north western cairn is visible as a platform 4.7m in diameter, levelled
into the slight westerly slope, without surface traces of a rubble core. The
platform's perimeter is defined by a kerb of at least seven closely-spaced
slabs, up to 1.25m long and 0.25m high, mostly edge-set but including one
large slab displaced inwards and lying flat on the platform's eastern sector.
The kerb extends around most of the platform, only leaving a substantial gap
at the south.
Within 150m of these cairns, other broadly contemporary monuments on St
Helen's include a further two kerbed platform cairns located near the northern
end of the same spur and a large round cairn containing a funerary cist
situated on the island's summit. Prehistoric field systems also occur on the
island's lower western slopes and on the higher slope east of the summit.
These 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.
