Dating project proves Norfolk's two Bronze Age Seahenges are same age

02 July 2014

Research by Norfolk County Council’s historic environment team has confirmed that Seahenge’s sister circle was made from trees felled in the spring or summer of 2049BC - exactly the same year as the first circle which was excavated in 1998-9.

The tree ring dating (dendrochronology) project carried out over the past year provides further proof that the construction of the two 4000 year old Bronze Age monuments at Holme Beach on the North Norfolk coast, believed to be connected to ancient burial rites, must have been directly linked.

The second ancient circle was discovered at the same time as the famous Seahenge but unlike its sister was never excavated and was left intact at its original coastal location – exposed to the elements of sea and weather.

Since then, its gradual erosion has been closely monitored and recorded and the dendrochronology tests were carried out to collect important information before it was lost forever.

The project also means that the two timber circles are the only ones in the country to have been dated precisely by dendrochronology.

When first fully revealed by the sea the second circle was made up of four elements. At its centre were two oak logs laid flat. These were surrounded by an oval of oak posts with oak branches woven between them. On the eastern side of the monument there was an arc of split oak timbers. Surrounding all the other elements was an outer palisade of split oak timbers, with the timbers set side-by-side.

Since 1999 coastal processes have damaged the second circle. By 2003 all the woven oak branches had been lost and in October 2003 one of the central logs was washed away. The second central log was dislodged by the sea in March 2004. From 1999 to May 2005 and between December 2010 and December 2013 the sediments around the palisade timbers were gradually eroded, leading to the exposure of more of the circle’s timbers. This erosion and the loss of timbers prompted the dating project to collect important information before it was lost forever.

The scientific research project on the ancient timbers was carried out by Norfolk County Council’s Historic Environment Service, funded by English Heritage and undertaken with the agreement of site managers Norfolk Wildlife Trust and owners the Le Strange Estate.

David Robertson, Historic Environment Officer at Norfolk County Council who ran the Holme II dating project said: “The reasons why the second circle was built are not clear, but it may have formed part of a burial mound. The two central logs may originally have supported a coffin. The oval of posts and woven branches could have hidden the coffin from view before a mound was added, with the outer palisade acting as a revetment for the base of the mound.

“As the timbers used in both timber circles were felled at the same time, the construction of the two monuments must have been directly linked. Seahenge is thought to have been a free standing timber circle, possibly to mark the death of an individual, acting as a cenotaph, symbolising death rather than a location for burial. If part of a burial mound, the second circle would have been the actual burial place.

“We continue to monitor and record any discoveries on Holme beach but have no plans to carry out any further excavations.”

Toby Coke, Chairman of Norfolk County Council’s Environment committee added: “I never cease to be amazed at the wealth of archaeology and heritage that we have in Norfolk. This is an intriguing project that has been painstakingly carried out by the County Council’s in-house experts. It will leave us with a wealth of information and very good records about how our ancestors lived in times long past.”

Richard Bird Norfolk County Councillor for Holme added: “Holme is rightly proud of its ancient history. The first circle was removed with some controversy but, unlike the second circle which is not visible – it can be visited for all to see at the Lynn Museum. The site is now a haven of peace and sanctuary for our wonderful wildlife which is most appropriate for this special monument.”

Kevin Hart, Head of Nature Reserves at Norfolk Wildlife Trust said: “The quality of the wildlife habitat at Holme Dunes is reflected in the fact that it holds nearly every national and international statutory protection available. Norfolk Wildlife Trust requests that visitors respect this special reserve because of the many bird species using the beach at this time of year. This second wooden circle is below the high water mark and is currently buried under sand and is not visible.”

It is hoped the project’s results will be published in full in the near future.

Background information

In 2004 and 2013 archaeologists working for Norfolk County Council’s Historic Environment Service recovered sections of seven timbers from the second circle. The tree rings visible in these timbers were measured and compared to tree ring sequences from Great Britain and northern Europe. The measurements of the circle’s tree rings were very similar those from other Bronze Age timbers and were directly comparable to those from Seahenge.

Holme Beach forms part of Norfolk Wildlife Trust’s Holme Dunes National Nature Reserve, which itself is part of the North Norfolk Coast SSSI (Site of Special Scientific Interest), and is internationally important for wildlife, especially birds. The peat beds - the location of the two timber circles - are an integral part of the nature reserve. In particular the peat substrate provides important habitat for large numbers of marine invertebrates that, on exposure at low tide, are a rich source of feeding for a large number of wading birds; arguably the roosts are the single most important feature on the whole North Norfolk Coast and are vulnerable to disturbance.

Photograph shows Seahenge's sister circle in February 2003.

For political comment

Cllr Toby Coke (UKIP) Chairman of the Environment, Development and Transport Committee, on 07717 881289
Cllr John Timewell (Liberal Democrat) Vice Chair of the Environment, Development and Transport Committee, on 01692 535074
Cllr Martin Wilby (Conservative) on 07920 286618 or 01379 741504
Cllr Terry Jermy (Labour) on 07742 157967
Cllr Andrew Boswell (Green) on 07787 127881
Cllr Richard Bird (Independent) on 01485 532565 (spokesperson on flooding and ETD)

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