Flood defence work uncovers Prehistoric and Roman timber Causeway

Posted on Thursday 3rd August 2006

Archaeologists at the University of Birmingham have been called in to investigate some large vertical timbers that have been discovered on a site in Suffolk that could possibly have been an ancient causeway.

Contractors working on the Environment Agency’s multi million pound flood alleviation strategy for Broadland made the discovery of what is proving to be a very important archaeological site.

During the excavation of a new dyke on Beccles Town marshes, a number of vertical timber remains were uncovered that had clearly been sculpted by hand. Realising these were more than old timber fence posts staff from Suffolk County Council (SCC) Archaeological Field Services Team were contacted and subsequently identified a number of preserved timbers relating to a wooden structure, possibly an ancient causeway. Some Roman pottery remains were also recovered and samples of the timbers were removed for dating. The initial results were considerably more interesting and showed that all of the timbers sampled represented a different stage of the site, with phases dating from the Bronze Age, Iron Age and the Roman period.

SCC archaeologists called on Henry Chapman, Ben Geary and Andy Howard from the University of Birmingham’s Institute of Archaeology and Antiquity to work with them on the excavation, due to their expertise in wetland archaeology and deposits.

The timbers were discovered by contractors Edmund Nuttall Limited working for Broadland Environmental Services Limited (BESL). BESL are currently undertaking flood defence improvement works at Beccles Marshes on behalf of the Environment Agency as part of the Broadland Flood Alleviation Project, a long-term 20-year programme of sustainable flood defence improvements. As the ground has been disturbed, it was feared that the remaining timbers within the site would start to decompose. Following advice from English Heritage and SCC, BESL commissioned a full-scale archaeological excavation to record the remains and learn more about the structure.

With excavation work now nearly finished, experts have a much clearer idea of what they have found - and describe it as nationally or even internationally important. The results have so far been excellent and suggest that a wooden causeway more than half a mile long may have run from dry land on the edge of Beccles, across a swamp to a spot on the River Waveney.

A 30m long section of the causeway has been recorded with over forty in-situ timber posts uncovered to date. The posts are surrounded by woodworking debris and horizontal timbers, which possibly once represented a platform around the posts. At 5m wide, it was capable of carrying carts and was the Bronze Age equivalent of a motorway and archaeologists have been stunned to find that it was in use from the Bronze Age in around 1000BC, through the Iron Age and to Roman times and at least the 4th century AD.

The debris left around the site and the size of the timbers is testament to the construction and woodworking skills of our ancestors. The wet conditions of the site mean that organic material such as wood has been preserved exceptionally well so that they can see what kind of tools were used to cut them.

Jane Sidell, English Heritage Archaeological Science Advisor says, 'this is the first such structure to have been discovered within Suffolk, and is one of only a few in Britain, and as such is a nationally important find. It gives us an excellent opportunity to examine ancient, possibly ritual, use of the marshland, and how the marshes have developed over time'.

The excavation, by the joint team from SCC Archaeological Field Services and the University of Birmingham, will continue until the end of the week. It is hoped that with English Heritage’s support the site can be analysed and dated, with the results published later in the year.

Dr Henry Chapman from the University of Birmingham said: "It is certainly a dramatic cultural achievement. The nearest dry land is a long way away. You can put this on a par with any of the big monuments in terms of effort to construct it. Decking is the best way I can describe it. You have upright timbers which have flat poles placed on top of them, effectively making the rails underneath the joists. On top of that you have the planks. It is the sort of thing you can have carts on. It is extremely rare, there is nothing like it. The site also provides an insight into climate change, with evidence of the wet swamp gradually becoming drier.”

Dr Chapman added: "You have got a causeway which has been used for a tremendous amount of time, which is unique; we haven't got something like that. It has been added to over time to preserve it, which shows its importance to early Beccles. A desire to cross a wetland which is changing in its character throughout that time is just bizarre."

He added that the timbers still being intact in the wet peat was one of the most important things about it.

"To touch, the wood feels really hard, like it is modern. It is exceptionally rare to get this sort of preservation. It is extremely valuable in terms of the archaeology and the amount of information we will get from it on woodland management, how they used tools to work the wood, and climate patterns."

Once the excavation has been completed, what will happen to the archaeological remains uncovered as a result of the excavation will depend on the results of laboratory tests including dating of the timbers and palaeoenvironmental analyses. Mr Paul Mitchelmore of the Environment Agency said: "It would be fantastic if some of the artefacts could be put on display in the Beccles Museum to give local people a view of what is on their doorstep."

Mr Kevin Marsh, Technical Manager of Halcrow Group Limited added “the success of this partnering project is evident by the speed in which we have been able to agree and organise the archaeological excavation with the respective organisations in order to allow the assessment of the site and ultimately its preservation by record”.