day trips to Oxford, Cambrige and Stonehenge

Yes, all are great day trips out of London. A bus called the Oxford Tube runs from near Victoria Station to central Oxford pretty much every hour throughout the day, and back again. I believe a bus with a similar name runs to Cambridge, but that merits checking. Trains to Oxford leave from Paddington Station. Trains to Cambridge leave from Kings Cross Station (and, possibly, another station.) Train to Oxford is about an hour; to Cambridge about 90 minutes. Buses are about 50 percent slower due to traffic and their slower speeds. (Took the bus last time I went to Oxford and spent 90 minutes stuck in traffic on the motorway on the way back.) So, although buses are a bit cheaper, trains are faster. You don't want to spend an hour on a bus that you could be spending out and about. You can get to Salisbury, the town nearest Stonehenge, by train from Paddington. Getting to Stonehenge and back to Salisbury will take a bus or cab. Salisbury is, itself, well worth a visit. The Oxford Station is about a 10-minute walk from the city center. The Cambridge Station is about a 30-45 minute walk, so catching a local bus or a cab might be appropriate. The buses depart from typical on-street bus stops, not stations, so you need to check the signs to be sure you are at the right stop. The Oxford Tube makes at least 3 stops in Oxford. If you are aiming for the city center, make sure you get off at the right place.

All are worth it. Stonehenge can easily be combined with a trip to Salisbury. The cathedral and cathedral area are really fantastic. I enjoy Stonehenge, very awesome place. Try and also see Avebury while you are there- you can walk up and touch the stones. Both are better if you arent running on atime table, so you can enjoy them as long as you are in the mood. I would even suggest overnight in Salisbury if you can. You can get tours to all three from London, but there are time constraints. Also train is easy. Cambridge you can walk the colleges and "the backs" (riverside) on your own. Oxford, is a busy town- you can see more if you can find a local tour to take you through the colleges. Salisbury/Stonehenge do not need a guided tour.

You don't spend more than an hour at Stonehenge so Stonehenge on its own will not be a full day trip. For Stonehenge its a lot cheaper and quicker if you just take a half day tour from Premium Tours or Evan Evans which both do Stonehenge only trips from London, morning or afternoon. Rail to Salisbury then the Stonehenge tour bus is both slower and more costly. However, Salisbury is a great place to visit if you fancy that combo and make a day of it.
Personally I would opt for the inexpensive Stonehenge and Bath tours for about 39 GBP where you see Stonehenge in the morning and have 3.5 hours to independently explore Bath in the afternoon. Not really a tour as such just a very cheap and effecient way of being transported to both places in one day and includes Stonehenge admission as well.

If you do the one day tour that gives you afternoon in bath, there are free guided tours around the town that leave from the Cathedral and are very worthwhile, I think it takes about an hour and would not miss it

I suggest google "London Walks".We went on tour to Oxford and also to Bath using the London Walks company and were quite pleased...

Agree with the London Walks suggestion. I have done 3 of their Explorer Days and they go to the locations you want to go to. They're very organised, you meet at a mainline station ticket office in the morning and go out on the train. On the 3 trips I did they have a bus waiting for you at the other end to get you about, the bus drops you off at places and picks you up again throughout the day. The 3 walks I did were all with different guides and all were excellent.

I agree with JC and others - take the train to Salisbury. Salisbury itself is a great day trip, especially if you go on a market day. You can catch a tour bus that runs a route to Stonehenge and Sarum (ancient Salisbury) at the train station or downtown. Salisbury and Stonehenge together was a great day trip, and the train was much more enjoyable than a long bus ride.

Take the train from Kings Cross to Cambridge. Definitely worth a daytrip. Once there you can walk into the city or catch a city bus right in front of the train station. The core of the city is very walkable. You can explore the colleges and don't forget the wonderful Fitzwilliam Museum (no admission charge but donation appreciated).

All worth it however Oxford and Cambridge are both university towns so just do one. Stonehenge can be a little diff to get to might be worth a tour from London to incl Bath. University towns you can do easily by public bus from London . enjoy they are terrific places to visit.

I highly recommend Alan Price of Celtic Horizons (RS recommends) for excellent visits to Oxford and Stonehenge. He took 3 of us there and we had the best day of our whole trip with him. He picked us up at the train station and dropped us off at the end of the long day (took the last train back to London). He is great at helping you plan a trip, too.

We have stayed at the Crowne Plaza (Kensington area) in May of 2009 and 2010. We will be staying there again in September. We took the tube out to Cambridge and to Oxford. We didn't care for Oxford. One of our tour books said if you can pick just one place, make it Cambridge. We should have followed their suggestion. After taking the tube to Cambridge, we took a hop-on, hop-off bus around Cambridge. They even have a beautiful mall there. As far as day trips, we have always enjoyed the Gray Line bus tours. We have used Gray Line in Rome, Paris, London, Boston, New York, Australia, Canada, etc. You can book the tours on-line here in the U.S. or after you get to a particular city. We have always had good experiences with Gray Line. Elaine

Despite repeated postings to the contrary from Elaine- the London Underground does not go to Oxford or Cambridge. But she does keep using this site to advertise a certain tour company