Sir – I’m sure that many readers already know that over-60s bus passes will get them free travel to Cambridge by coach.

It is probably less well-known that the Oxford Tube can be used free for travel between Oxford and Lewknor, very useful for walking in the Chilterns. But surely less well-known of all is that the X90 can be used free between Hillingdon and Victoria.

This may leave one wondering how to get from Lewknor to Hillingdon by bus. It can be done in 2½ hours changing at High Wycombe but this is possibly not the best idea because you can get from Oxford to High Wycombe in 1½ hours by bus anyway without bothering about Lewknor at all.

There are, in fact, various ways of getting to Hillingdon by bus from Oxford in about three hours and indeed, no doubt other ways of getting to London by bus without going to Hillingdon.

Roger Moreton , Oxford