Sir – Cassandra Barrington-Harness’ letter (August 11) gives an opportunity to remind people of the ‘Open Doors’ weekend (September 10-11) in which, of course, Oxford University and the colleges will be participating. In the same spirit, they provide much else free all the year round: museums, parks, meadows and indeed access to some colleges.

There are schemes to provide free access for locals; we have one in Christ Church. Our prime purpose is, however, educational and intensive study requires quiet and security which would not be possible were there to be a free-for-all.

The University has recently produced a helpful map with the title ‘Explore the University of Oxford’, for locals and visitors alike.

Christopher Lewis, Christ Church, Oxford