OPENING Doors, Opening Minds might sound like yet another Oxford University bid designed to tempt youngsters from northern comprehensives to apply to Oxford.

But it is, in fact, a remarkable chance to enjoy many of Oxford's hidden treasures, being opened to the public this weekend as one of the highlights of Oxfordshire's millennium celebrations.

More than 25 sites and buildings will offer the public behind-the-scenes glimpses of some of the city's most fascinating places.

From today until Sunday, Opening Doors, Opening Minds will see colleges and museums staging one-off events and activities, from music and drama to trails and special tours, and hands-on activities for children.

You can enjoy a family picnic at the big Summer Picnic at the Botanic Garden or in the gardens at Headington Hill Hall, with its rich history and links to both the Morrell and Maxwell families.

There will be opportunities to look backstage at the New Theatre, Oxford, learn more about real tennis with a tour of the real tennis club at Merton College or take a ride on a vintage bus to the Oxford Bus Company and explore its depot.

Sports fans will be able to see oarsman Matthew Pinsent's four Olympic rowing gold medals on show at St Catherine's College.

And a series of concerts are being staged at less familiar venues, including a performance by young musicians from the Oxfordshire Music Service tonight in the outdoor amphitheatre, pictured, within the Said Business School.

Tickets are free but must be booked by ringing 01865 280533.

The events have been organised by the Oxford Preservation Trust in partnership with Oxford University, with funding from the Heritage Lottery Fund.

Opening Doors, Opening Minds was fittingly launched at Oxford Castle on Monday, when guests were treated to jam made by children from Oxford Community School.

The youngsters have been studying Coopers Jam Factory, one of Oxford's great success stories.

And Oxford's great jam story, which began with a few pounds of Seville oranges being boiled up by a grocer's wife, will figure prominently over the weekend.

A blue plaque now marks the building where Sarah Jane Cooper created her famous marmalade in the outbuildings behind number 83 High Street, a Corinthian-pillared shop close to the Examination Schools.

Unfortunately, Frank Cooper's Oxford Marmalade is no longer made in the High Street, nor at the Jam Factory, Park End Street, where the Coopers moved production in 1903.

The Oxford label remains, however.

Tomorrow, the Oxford Community School youngsters will be offering jam for tasting at the Westgate Centre.

Children will be involved in some of the weekend's other highlights.

Local schoolchildren will be taking part in a water-based science project in the famous hall at the Oxford University Museum of Natural History, the site of the Royal Society's debate on Darwin's theory of evolution.

Young speakers will today be taking part in a debating competition at Convocation House, now part of the Bodleian Library, once used as a Royalist Parliament during the Civil War.

And schoolchildren are also being invited to design gargoyles for Oxford's world-famous Bodleian Library.

Up to ten of them will see their gargoyles turned into stone and placed on the north-west face of the 16th-century library, from where they will look down on the city for centuries to come.

Anyone studying, living or working in Oxfordshire, between the ages of eight and 18, is invited to submit a sketch of a gargoyle design.

The idea must be based on one of three themes - myths, monsters or people - and have a historical connection with Oxfordshire within the last millennium.

Tomorrow a stonemason will be at the Sheldonian Quad, Broad Street in Oxford from 10am-4pm to demonstrate his skill and show how he can create shapes out of stone.

The designs need to be drawn on a leaflet provided at the Opening Doors, Opening Minds venues.

The leaflet can also be downloaded from the website ox.ac.uk/publicaffairs/gargoyles The competition is open until September 1 and entries need to be sent to Design a Gargoyle Competition, Public Affairs Directorate, University Offices, Wellington Square, Oxford, OX1 2JD.

For a list of events, click here.