london to oxford?

You can take the train from Bath, one change at Didcot Parkway. The colleges are definitely worth seeing - you can take a tour from the T.I. The Ashmolean museum is also worthwhile. It's a good town for just wandering around. See http://www.visitoxfordandoxfordshire.com/

Also very easy to train from London.

Like Bath, Oxford is a university town with lots of non-tourist stuff always going on. Just look at the noticeboards while you're there.
Also like Bath, Oxford is quite a good base to explore the region independently, especially the Cotswolds, Blenheim Palace and Stratford Upon Avon There is a daily evening bus from Bath to Oxford with National Express which if you buy tickets on-line are typically around $US10 or less, much cheaper than the train

Leaving tomorrow, the train takes an hour to an hour and a half, runs every hour, and costs 14.70 GBP. There's only one direct bus, in the evening as Bob says, and costing 7.50 but taking 2 hours. While you can take the train from London, there are also buses, with the "London Tube" (not the underground) and the Oxford Bus Co. However, checking fares for tomorrow turns up a very surprising 4 GBP on one direct train! Pick the wrong train and it costs 21.40 - clearly pays to spend some time on http://www.nationalrail.co.uk/

Visit Oxford! It's lovely - charming - delightful! Bath is about an hour and a half by car from Oxford. There's also a regular bus - takes about 2 hours. I am not sure about the train. When in Oxford, besides walking the grounds of the colleges (and you should check the rules and hours for each college - try here: http://www.tourinaday.com/oxford/oxford-university.html) you can: Visit the Bodleian Library: they have lovely temporary exhibits, and amazing old books on display. Take a punt out on the river. Here's the local daily guide, with instructions: http://www.dailyinfo.co.uk/guide/punting.htm Shop along Broad Street and the High Street: http://www.dailyinfo.co.uk/guide/shopping/index.html Enjoy an excellent pint at the Eagle and Child, the pub where J.R.R. Tolkein and C.S. Lewis met to drink and discuss their work! Check out the Rabbit Room - the actual room where they met. This is, in my humble opinion, one of the most charming and delightful pubs in all England. Wiki says: http://en.wikipedia.org/wiki/The_Eagle_and_Child