Proposals to restore Lichfield Cathedral's position as one of England's great cathedrals have made progress with the recent acquisition of a building in the Cathedral Close for a learning centre and proposals for the restoration of the historic lime avenue.

It has also been announced that the Cathedral will feature on a new Royal Mail 1st Class stamp next spring.

Birmingham-based Kinetic-AIU, an innovative architects' practice which specialises in creating sustainable buildings, has been brought in to see through the changes.

Following an open-competition, which attracted entries from leading practices across the country, they have been appointed to draw up plans for an improved visitor experience at the Cathedral.

The appointment comes just six months after the Cathedral first published interim plans for the new development but Cathedral authorities say those plans were not ambitious enough. They are now looking to further enhance the visitor offering with the creation of a discovery zone which will utilise all the space between the existing restaurant and visitors' centre.

This area will bring together the Cathedral's trading and catering activities into one place and house all services to visitors and pilgrims. The existing Cathedral shops, currently located within the Cathedral and at Number 9 The Close, will be transferred to this area.

In the original plans this area would have also housed a new educational centre to develop the Cathedral's post-graduate facilities. This will now be housed on the ground, first and second floors of number 20 The Close, after the Cathedral recently acquired the first floor of the building. The Cathedral hopes this will provide a much greater space for learners of all ages.

As part of the development plans, the Cathedral is creating a number of new posts and increasing the total number of staff by six. It is also introducing a 7-day week operation to visitors.

The Cathedral Close is home to the second-oldest avenue of lime trees in England. The 'Dean's Walk' dates back to 1703 and is pre-dated only by the lime avenue in Windsor St Paul.

The 'Dean's Walk' was a favourite walking place for Dr Samuel Johnson but the trees are almost at the end of their life and the Cathedral is working with Lichfield District Council to find ways of replacing them with new lime trees to ensure the avenue is restored for future generations to enjoy.

News of the developments came as it was revealed that Lichfield Cathedral will take prime position next May on a new series of Royal Mail stamps featuring great cathedrals across the UK. Lichfield has been given prime position on the first class stamp meaning it will be seen by millions of people across the UK and attract thousands of new visitors to the cathedral and city.

The bulk of the building work will take place in 2010 but should begin next April with two years of restoration work on damaged high-level stonework over the south choir.

The restoration work will continue until 2016 when all the historic Herkenrode windows in the east end have been restored. But the cathedral hopes the bulk of building work will be completed by Easter 2011 to coincide with the 400th anniversary celebrations of the King James' Bible and the Regional Cultural Olympiad.

The Dean of Lichfield, the Very Rev Adrian Dorber, said the Cathedral community were very excited by the latest plans: "We have been encouraged to 'think big' and remember that we are stewards of a major national cathedral, not a small city church and we must plan, work and act accordingly.

"We no longer understand Lichfield Inspires as a project about conservation, interpretation, access and education. Rather, we believe that these are the building blocks enabling us to pursue our mission - our way of life. The practical aspects of conservation, interpretation and new buildings are merely the stage for the Cathedral's expanding ministry to large numbers of pilgrims, visitors and learners."

He said the next two years will see the Cathedral enter into an experimental phase while work is undertaken with Staffordshire University to develop a "non-invasive way of interpreting the Cathedral to our multi-national visitors".

He added: "We want to de-clutter the Cathedral and allow it to stand tall as a magnificent sacred place for tourists and visitors; and over the next two years we will 'fine-tune' our plans for working with double the number of visitors and pilgrims."