Dr Donna Jackson called her talk 'I Believe in Yesterday'. She explained that it was not about the Beatles, but about the phenomenon of Beatles Heritage in Liverpool - and, more particularly, Woolton/Gateacre.

What is heritage? 'Anything that matters to us - that we'd miss if it wasn't there'. It is the 6th biggest industry in the UK. Over 3 million people a year cite the Beatles as a reason for visiting Liverpool; and they spend an estimated £400 million a year in the city.

It was John Lennon's death in 1980 - ten years after the Beatles broke up - that started the 'pilgrimage'. There are now statues, themed hotels and the Beatles Story exhibition. The new Museum of Liverpool includes a corner of the stage from St Peter's Church Hall, Woolton - including the wooden steps where John first met Paul. There are tours - some good, some not so good.

Strawberry Field was a Salvation Army children's home on the edge of Gateacre and Woolton. When Strawberry Fields Forever was released in 1967, John explained that he - having lost his mother as a teenager - had identified with the orphan children. Its gates are now a stopping point on the daily Magical Mystery Tour of Liverpool. The Salvation Army is hoping to reopen the building (closed since 2005) as a training school, to improve the lives of people with learning difficulties, funded by a heritage centre and café. Donna is their consultant and (without giving away too much about the plans) she discussed its 'authenticity' and 'aura'  - concepts which are crucial to an understanding of the heritage industry.

Beatle fans, she said, want to 'walk in the footsteps of their heroes'. They respond to the Cavern Club, a 1980s rebuild. They photograph the replica gates at Strawberry Field, installed because fans were destroying the originals. The gates weren't even featured in the Strawberry Fields Forever video, but they've become the symbol. Will the stone steps in the grounds, 'which John must have run up and down', and the woods 'where John must have played' come to have the same attraction?

Some visitors to Liverpool are mere tourists ('who go somewhere because they feel they should') but others are pilgrims ('who have a personal reason for going, a connection'). Donna argued that Strawberry Field and St Peter's Church Hall both have an 'aura' - once visitors have been made aware of their significance.

Beatles tourism has benefits. It makes people happy, it brings income through souvenir sales and church donations. But it also has disadvantages - intrusion, damage, traffic. People walk over graves at St Peter's, on their way to that of 'an' Eleanor Rigby. Donna suggested that there is a need for official regulation. Some guides are well trained and qualified - knowing how to keep the neighbours, not just the visitors, happy - but others invent stories, or fail to control their clients.

When Donna invited questions, one of the first was about John Lennon's supposed connection with Gateacre. He has said to have lived there (age 5) with his mother Julia, in 'a small flat in a large house'.  Where was it exactly? This led to a question back to the audience: if it was your house, would you want people to know that John had lived there? Would you want the Magical Mystery Tour to be extended into Gateacre village?

Donna's talk, and the subsequent discussion, gave us much food for thought.