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Post-medieval smugglers' cache at Porth Mellon, 110m west of Harry's Walls Battery, St Mary's

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

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Latitude: 49.9184 / 49°55'6"N

Longitude: -6.3081 / 6°18'29"W

OS Eastings: 90865.622838

OS Northings: 10920.30792

OS Grid: SV908109

Mapcode National: GBR BXTW.TN5

Mapcode Global: VGYC4.M90X

Entry Name: Post-medieval smugglers' cache at Porth Mellon, 110m west of Harry's Walls Battery, St Mary's

Scheduled Date: 21 January 1999

Source: Historic England

Source ID: 1015668

English Heritage Legacy ID: 15483

County: Isles of Scilly

Civil Parish: St. Mary's

Built-Up Area: Hugh town

Traditional County: Cornwall

Lieutenancy Area (Ceremonial County): Cornwall

Church of England Parish: Isles of Scilly

Church of England Diocese: Truro


The monument includes a small stone-lined smugglers' cache, a hidden store
for contraband goods, dating to the 19th century and situated behind the north
east cliff of Porth Mellon on the west coast of St Mary's in the Isles of
The smugglers' cache is visible as a short underground passage, 5m long, up to
0.9m wide and 1m high, cut NNW-SSE behind the upper cliff of Porth Mellon.
From a flat silt-covered floor, the sides of the passage rise vertically,
faced by six courses of slabs and cobbles, some roughly shaped but not dressed
flat. It is roofed by long slabs laid across the passage, resting at each end
on the coursed facing. Some facing and roof slabs bear drilled holes along
split edges, showing a stone-splitting method that appeared in general use
c.AD 1800. The passage curves slightly southward as it progresses to its SSE
end, to which the floor also descends gradually. At the SSE end itself, the
stonework of the passage sides and roof ends abruptly at a layer of soil and
rubble through which a roughly dug access pit rises steeply to the surface.
Fragments of 19th century pottery occur in the soil partly collapsing into
this pit.
The NNW end of the passage opens directly onto a turf-covered ledge in the
upper cliff; the south west wall facing extends 0.7m beyond the NNW lintel
indicating some robbing of larger stones from the original NNW end of the
passage. The exposed section across the passage at this end reveals how it was
built. The passage was originally dug as a trench, 1.8m wide and 1.8m-2m deep,
cutting deeply into the orange subsoil. The coursed facing walls, 0.5m thick,
were then built along the sides of the trench and the roofing slabs were laid
across. The resulting structure was then covered by redeposited subsoil, soil
and rubble, infilling the trench and merging it with the surface profile of
the surrounding coastal margin.
This smugglers' cache is located beside the broad bay of Porth Mellon, facing
the islands' main sheltered anchorage of St Mary's Pool and close to the focus
of the islands' population and trade at Hughtown, 0.3km to the south west. It
is also at a point on the coastal margin hidden from view from many angles,
and from most of Hughtown by the small coastal promontory of Carn Thomas and
the ridge extending south east from it.

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.

Smugglers' caches are hidden stores where contraband goods were concealed from
the authorities, potential informants and rivals. Rising trade, demand and
taxation affecting imported commodities such as tobacco, spirits, and tea
during the 17th and 18th centuries, coupled with few effective controls on
maritime activity outside the major ports, encouraged an illicit trade by
smugglers profitting by avoiding payment of duty on goods run across from the
Continent or acquired at sea from trading vessels in the Channel. Trade in
contraband goods was especially rife along most of the south coast of England,
facing the Continent; some small ports and coastal villages in Kent, Sussex
and the south west achieved notoriety for their smuggling activity, involving
large numbers of vessels and men and forming a significant part of the economy
in some areas by the mid-18th century. Early counter-measures included a
network of Customs Stations whose collectors controlled Revenue Cutters,
sometimes supplemented by naval vessels. Despite some limited success, their
resources were too thinly stretched and could not match the local knowledge of
the coastline of the smugglers. Increasingly effective control only came with
the ending of the wars with France when, in 1816-17, the Customs was
considerably expanded to include the new Coastguard, with sufficient manpower
to operate as a widespread preventative force along the south coast. In
conjunction with stringent penalties, including the destruction of vessels
caught engaged in smuggling, the trade in contraband goods had been severely
reduced by the 1840s. Accounts of successful anti-smuggling actions by Customs
and the Coastguard forces reveal a variety of ingenious methods adopted in the
early 19th century to conceal smuggled goods after their arrival and before or
during their distribution, reflecting the increased pressure on the smugglers
activities. In addition to securing the contraband beneath the surface of the
sea, fixed to weights on the sea-bed, other favoured sites of temporary
storage included hidden caches constructed within, beneath or near dwellings
or public houses used by the smugglers.
Until the establishment of the Coastguard, conditions in the south west of
England proved especially favourable for smuggling, with its deeply indented
coastline remote from the centres of authority and administration but
conveniently facing the Continent and adjacent to the trade routes entering
the Channel. The enhancement of these factors in regard to the Isles of Scilly
was used to advantage by many among its population, as is testified by the
repeated complaints of successive Customs collectors based there. The
importance of smuggling as a vital supplement to the islands' economy of the
18th and early 19th century is shown by a petition in 1819 to relieve the
islanders' poverty, citing the effectiveness of the new preventative force as
a main cause of their distress. Apart from historical references and
association with some surviving buildings on Scilly, this formerly important
activity leaves relatively few remains, chief among which are smugglers'
caches and a series of 19th century lookout points set up and used by the
Coastguard force. Three smugglers' caches are known to survive on Scilly, one
on St Mary's and two on Tresco. Each is visible as an underground passage in a
hidden location separated from nearby dwellings and each is of differing form.
The number of such smugglers' caches that survive nationally is not known and
by their intentionally-concealed nature, more are likely to survive than have
been recorded. Smugglers' caches provide one of the few surviving remains of
an activity which demonstrates the interplay of developing trade and law
enforcement efficiency during the post-medieval period.
The smugglers' cache at Porth Mellon survives well, retaining clear evidence
for its manner of construction, and it is the largest example of such a cache
on Scilly. Its concealed siting is typical but it is the only known surviving
example located in such close proximity to the main anchorage and centre of
population on the islands. Its 19th century date, evidenced by the
stone-splitting method employed, reflects the increasing pressures from the
authorities at that time which resulted in the need for such caches.

Source: Historic England


Books and journals
Ashbee, P, The chambered Tombs on St Mary's, Isles of Scilly, (1963), 9-18
Ashbee, P, Ancient Scilly, (1974)
Gerrard, S., English Heritage Book of Dartmoor, 1997, Forthcoming
Parkes, C, AM 107 for Scilly SMR entry PRN 7569, (1988)
Title: 1:2500 Ordnance Survey Map; SV 9010
Source Date: 1980

Source: Historic England

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