The last time such a crowd would have gathered around the coffin lid would have doubtless been for the funeral of the person interred beneath it 800 years earlier.

More than 100 curious onlookers came from all parts of the county to isolated St Mary's Church, Fishley, near Acle, yesterday to watch history being literally uncovered.

Soil in the churchyard was carefully brushed away so leading church historian Dr Julian Litten could examine the lid for clues as to who had been buried at a time when the church - now stranded lonely on a pinnacle amid fields of corn - was at the heart of a wealthy estate by the sea.

It is a mystery that has consumed church warden Ivan Barnard, 68, since a much smaller coffin lid was found in tall grass by the tower 21 years ago.

Combing through parish records the retired MoD technician discovered it was one of possibly three which had been moved out of the church during structural renovations undertaken in the 1860s by then estate owner Sophia Edwards.

It was not until last August when, noticing an arid patch in the churchyard, he tapped the ground and discovered where a second coffin lid - twice the size of the first - had been moved to.

His excitement grew when he realised that the stone coffin beneath it was also still there, unlike the case of the first lid - now displayed inside the church - when the coffin itself was never found.

Dr Litten, a world-leading authority who oversaw the burial of the unknown mariner from the Tudor ship Mary Rose at Portsmouth Cathedral in 1984, was invited to examine the lid in an event to celebrate Open Churches Week.

To help his research, Mr Barnard, of Fishley View, Acle, sent him detailed photographs of the site in advance.

Dispelling one romantic notion that the person might have had a personal connection with King John - said to come hunting at Fishley during his reign from 1199 to 1216 - he concluded nevertheless that the lid would have certainly concealed the final resting place of a wealthy lord of the manor.

Dr Litten, of King's Lynn, said: 'The burial would have taken place some time between 1250 and 1350. The lid is made of Purbeck marble and would have been specially ordered and brought round the coast from Dorset by barge to the nearest off-loading station.'

He said a temporary stone lid would have been put in place initially with the marble lid replacing it possibly a year later once it had been ordered and made.

Dr Litten said a variety of styles of crosses would have been available to decorate the lid, but it was too corroded to tell which type had been chosen in this case.

He speculated that if there were three such coffins, they might have been for a mother and father and child.

Following the hour-long examination, Mr Barnard confessed he was 'over the moon' that so much had been gleaned by Dr Litten.

He said that to take the investigation even further and open the coffin for examination a special legal order from the church would be required.

That would be a costly and complicated exercise and would certainly need sponsorship if it were ever to happen.