Day trip tours out of London

London Walks do day trips out of London. Walks.com. I know they do trips to Bath. Dont know if they do one in your timeframe. I haven't been on their Bath trip but would recommend them based on other trips I have done. You can get to both destinations by train. However, at the moment its snowing here + the February weather forecast is not good and the transport system may not be altogether reliable.

What would you like to see in Dover? Port? France? Castle? Manky B&Bs? (sorry about that - its just the worst B&B I ever stayed in was in Dover) Cliffs? What causes the interest?

The castle with the war tunnels as well as the cliffs are the main draw for us.

The Castle, which has the tunnels, is operated by English Heritage. I've been around the tunnels which are most interesting. The difficulty is the opening hours at this time of year. I hope this fits your plans. Its only open Saturdays and Sundays during the winter. During the school holidays next week, 13th to 17th February, they will be open all week. The other thing is the cliffs. When you are in Dover you are on top or around the headland from the cliffs. They are not really visible, not what you would most likely expect. I prefer the view from the top of Beachy Head in the Seven Sisters, down the coast the other side of Brighton (mind you don't fall off, though). If you really want to see the White Cliffs of Dover they are best seen from the sea. I have done that on the Dover/Calais ferry. I wouldn't want to be out in the Channel in February, especially with the weather being the Siberian Express we are suffering from at the moment. I don't want to cast cold water on your plans, but I want you to be prepared.

London Walks are the best. Show up with money and go. They take care of all of your train tickets and bus transport. They also give you some time on your own for lunch and exploring. Our guide, Richard, was really impressive. We went to Salisbury and Stonhenge one day and Oxford and the Cotswolds the other.

If you want to see Dover, Canterbury and Bath specifically its best to do go independently rather than take a tour. If you need a guide the local ones are superior to the ones from London. The 'free mayors walking tour' at Bath lasts 2 to 3 hours' which sets you up very nicely discovering Bath in the afternoon/evening before getting a late train back in the evening. The big 3 tour companies that do the big bus tours are Premium, Evans Evans and Golden tours, everyone else is an agent of one of these. On these they try and do 3 places in a day which means no longer than 2 hours in any place.
Only Premium visit Dover Castle and Canterbury. The 'quality' tours are operated less frquently by International Friends and London Walks but frankly for the 3 mainstream places you want to visit you'll get better value, quality and more time going independently.