By John Venables

Research documents which chronicle one of Europe's most important Bronze Age excavations have been destroyed by fire - in a mouse nest.

Flag Fen, near Peterborough, UK, was discovered under fenland farmland 18 years ago.

The site, which comprises a mysterious wooden platform the size of Wembley stadium had lain undisturbed since 900 BC.

The site is unique in Europe and its excavation has been a focus for archaeologists from all over the world.

Almost two decades of research work into the site has been destroyed after routine maintenance work accidentally set light to an empty mouse nest. The resulting blaze destroyed the entire building.

Serious damage

Staff at the Flag Fen research centre are still too shocked to be able to evaluate the damage, but they say very little can be recovered.

"The problem is that while some records have survived they're badly singed around the edges, and that's where the identifying marks and numbers were. So although some documents have survived the fire, most of them are now scientifically useless," said Toby Fox, Flag Fen's general manager.

The records were contained in fireproof cabinets, but the heat was so intense the cabinets burst open.

Ironically all the records had been copied and the duplicates were kept in another building, but because of damp they had been temporarily moved back. As a result the only copies that remain are in published work by the centre's founder Dr Francis Pryor.

Photographs too were destroyed and the centre has issued an appeal for anyone who has copies of either written work or photographs to get in touch.

Seahenge saved

Flag Fen is also the home of the so-called Seahenge timber circle, recently recovered from a Norfolk beach, despite bitter opposition from some local people and druids. Fortunately, the Seahenge remains were kept in water tanks in another building some distance away and were not harmed.

It would have been an even bigger blow to the archaeologists if the fire had affected the Seahenge artefacts. One of the reasons they gave for moving the circle from its exposed site on a beach was that the circle was in danger of being destroyed.

Flag Fen lies between two Bronze Age settlements. Despite almost 20 years of work archaeologists still have little idea what the enormous timber raft could have been. Tree ring dating suggests it was occupied between 1350 and 900 BC. One theory is that it could have been a religious site.