Rare Roman anchor from North Sea windfarm site comes to Ipswich Museum

By Anna Mercer, Senior Collections and Learning Curator

For one day only, on Tuesday 27th September, visitors to Ipswich Museum will be able to see a rare Roman anchor, which was discovered during the construction of the East Anglia One Windfarm site off the coast of Suffolk.

The iron anchor found by ScottishPower Renewables during the construction of the East Anglia ONE offshore windfarm is currently believed to be a rare example of a Roman or possibly late Iron Age anchor, somewhere between 1,600 and 2,000 years old. Due to the size, it has been estimated as belonging to a 500–600 ton vessel, a significant size of vessel for this early period.

There are currently only three pre-Viking anchors known from northern-west European contexts: at Bulbury Camp (excavated in 1881 and likely to date to the 1st century AD), Priestside (found in 2019 – date not confirmed) and Nydam in Denmark. Only the first two of these still survive. No such anchors have been recovered from marine contexts outside the Mediterranean, which would make this the first discovery of its kind from Northern seas.

The anchor has undergone conservation by the Mary Rose Trust, which has allowed for a greater understanding. The current length is 2.36m, but the anchor head is broken so there is no surviving loop or eye for a rope. The shank is square with a slightly pointed crown and straight arms that sweep upwards (one of the arms was already broken prior to retrieval).

The anchor after initial conservation by the Mary Rose Trust in Portsmouth

While robust iron anchors of the 18th and 19th centuries are relatively common, this iron example is of a type and shape that is likely to be of pre-Viking origin. The pointed crown and rectangular cross-section are all characteristic of a Roman anchor.

During the Roman occupation of Britain, from AD43 to AD410, there were advances made in the design of Roman ships for safer travel across the turbulent and sometimes violent seas of the English Channel. Ships were constructed with shallow hulls that would enable the navigation of coastal waters, and high bows and sterns to traverse heavy seas. The ships used at this time would have been a combination of war ships and merchant/ transport ships.

The anchor on the sea floor

A range of merchant vessels were used throughout the Roman empire with cargo carrying capacities ranging from 70 tons to 600 tons. Merchant vessels were much larger than warships and, to maximise cargo space, did not have teams of rowers in addition to sail power. Records of these ships outside Mediterranean waters is sparse, but there are examples including a graffito of a Corbita (a large merchant ship) in a Gallo-Roman house in the French town of Cucuron. There are a few examples of shipwrecks of Romano-Celtic build from northwestern-Europe. One is that of a ship discovered along the River Thames at Blackfriars in London, which has been dated to the middle of the second century AD. Evidence of shipworm in the hull timbers shows that it had been a seaworthy vessel. Another is a Roman ship of the first century BC wrecked off the coast of Gaul, which was 130 feet long with an estimated capacity of 440 tons.

Maritime archaeology specialist, Keith Muckelroy, writing in 1978, highlighted how unusual a find of an early anchor around Britain, such as this Suffolk one, would be: ‘The chances of ever identifying an Iron Age anchor in British or northern French waters would seem to be remote, since one would only have survived over such a period in very exceptional circumstances’.

The anchor being lifted from the water

Its discovery off the coast of Suffolk is testament to the long history of North Sea trade between Suffolk and the Continent, a trade on which the port and town of Ipswich was founded in the Anglo-Saxon period; and of course to the careful maritime archaeology work undertaken alongside the construction of the East Anglia One windfarm site.

Ipswich Museum is proud to be able to display this unique and important find for this one day, after which the anchor will be returning to the Mary Rose Trust in Portsmouth for further conservation. We expect the anchor to eventually be return to Ipswich Museum, where it will become part of new displays in the Ipswich Museum redevelopment project.

The majority of the information in this blog is drawn from a briefing paper prepared by Brandon Mason of Maritime Archaeology Ltd, who undertook the maritime archaeology work on the windfarm site, with the support of Scottish PowerRenewables. Colchester + Ipswich Museums are grateful to both organisations for permission to use this information. Further information on historical/ archaeological sources is given in Brandon Mason’s original paper.