A museum in King's Lynn, Norfolk, has temporarily closed to the public in order to allow the central stump of a historic Bronze Age timber circle to be installed at the attraction.

Lynn Museum reopened in April 2008 following the completion of a major revamp to create a gallery devoted to the 4,000-year-old Seahenge structure, discovered at Holme-next-the-Sea near Hunstanton in 1998.

Excavated timbers have undergone an extensive preservation process funded by English Heritage, which has involved the removal of beach mud and marine salts, as well as immersion in a synthetic wax to reinforce the wood.

Although a number of timbers have already been put on display at Lynn Museum, the central structure will also be installed on a bespoke mount at the attraction and will feature next to a full-size replica of how the timber circle would have appeared.

Norfolk County Council's cabinet member for cultural services, Derrick Murphy, said: "Why our ancestors built Seahenge remains a mystery, yet we can state categorically that it is one of the most significant historical discoveries ever to be found in Britain.

"The installation of the central stump within the gallery at the Lynn Museum marks a fitting end to this chapter of the story of Seahenge. We are certain that the exciting display of this unique find will be of huge interest to both local people and visitors to the area."

The museum, which is operated by Norfolk Museum and Archaeology Service on behalf of NCC and district councils, is expected to reopen in early summer 2010.