Tresco Channel


Tresco Channel


Tresco Channel is a narrow stretch of water between the islands of Tresco and Bryher in the Isles of Scilly. The presence of medieval pottery in Tresco Channel has been known for some time. In 2011 a local diver (Dave McBride) recovered a quantity of medieval pottery while working on yacht moorings in the channel and brought it to the attention of CISMAS. This pottery was of French origin and dated approximately to the end of the 13th century. Later in 2011 a survey of the area was undertaken jointly by CISMAS and Promare. The survey recovered 269 fragments of medieval pottery from the seabed. This pottery was analysed and found to be predominantly from the Saintonge region of France almost entirely of late 13th – early 14th century date. The pottery distribution was mapped and shows a distinct concentration around two of the mooring buoys.

Potter 2011 survey


Potter distribution

Distribution of the pottery found by CISMAS in 2011. The circles show the areas searched


The narrow date range, restricted origin and confined geographical location of this pottery suggest a single event leading to its deposition. The most likely event would seem to be a medieval shipwreck. Given the date of the pottery recovered, any associated wreck material would be of great importance to our understanding of maritime Scilly, and any surviving hull structure would be of national importance given the scarcity of wrecks of this period in the UK. The full report of the 2011 survey can be downloaded here


CISMAS Excavation 2013

CISMAS divers excavating on site in 2013


In late 2013 an excavation was undertaken on the site by CISMAS, this work was funded by English Heritage. Details of the CISMAS team who undertook this excavation can be seen <here>. Four small trenches were excavated around the two moorings at the centre of the pottery distribution surveyed in 2011. A total of 914 objects were recovered from the excavation, of these 385 were pieces of medieval pottery, much of which was again from the Saintonge region of France. These finds are currently undergoing analysis; results will be posted here when this has been completed.


Finds summary 2013




Fragments of a French jug (F613) late 13th/early 14th century



F852 fragment of a Saintonge costrel late 13th/early 14th century (a costrel is a flask with lugs or small handles for suspension)



F623 Collared jug Probably French late 13th/early 14th century



F624 Late 13th/early 14th century baluster jug

Saintonge pottery is thought to have been imported to medieval England as a by-cargo of the wine trade. The large number of sherds originating from Saintonge in France leads to the speculation that these pots arrived in Scilly as part of the wine trade, the obvious candidate for such trade in Scilly being the nearby priory of St Nicholas on Tresco. This may even have been a trade undertaken by the priory on Tresco, as we know that the ‘monks of Scilly’ owned their own ship in the early 12th century.


Finds Recording

CISMAS members recording objects recovered in the 2013 excavation.

Other finds from the excavation include eight small wooden dowels; these are thought to be bale pins. Bale pins were used to secure bales of raw wool for shipment. These may be evidence of medieval wool trading – wool was an important export in medieval England. It is tempting to speculate that we are looking at a trade where wine is imported and wool exported from Scilly


Bale Pin
Lead-alloy spoon

F921 wooden bale pin


F920 Lead-alloy spoon

Buckle Leather Shoe
F648 Copper-alloy buckle F923 part of a leather turn-shoe


No articulated ship structure was found in the excavated trenches. However a number of iron nails (13) were found, some of them with attached roves. These are likely to have been used as ship fastenings. What the excavation has established is a refined epicentre for the pottery distribution. We now have a good idea of where this pottery distribution is centred and hope to investigate this further once funding has been secured for further fieldwork.


Sponsors of this project

Promare funded the joint Promare/CISMAS survey of Tresco Channel in 2011

English Heritage funded the excavation in Tresco Channel undertaken by CISMAS in 2013

3H Consulting provided assistance and Site Recorder the GIS used during the project

Ambient Pressure Diving donated consumables for the rebreathers used by some of the CISMAS divers on this project

Isles of Scilly Travel provided discounted travel for CISMAS to the Isles of Scilly

Otter Drysuits provided discounted dive suits for CISMAS divers