Neither one is "best". Both would be wonderful. So I'd just flip a coin.

Warwick - great medieval castle (but you probably won't have time to wander around the really neat little town.

Stratford-Upon-Avon - all the Shakespeare connections but really toruisty - especially if you are limited to where the tour takes you.

Oxford - a wonderful place - but I do suspect you won't have more than about an hour or two there.

Dover Castle - the most amazing site with everything from a Roman lighthouse to WWII tunnels.

Canterbury - a glotious cathedral and interesting town.

Leeds - REALLY lovely gardens/grounds - not much inside.

Both would be fairly rushed trips - but you gotta do what you gotta do . . . . .

OOPS - that should be "glorious" cathedral . . . .

I went on the Canterbury day trip with EvansEvans this June. I enjoyed, but I can't compare to Oxford and Warwick. I would say make your decision on the castles. Would you rather see a real medieval type castle(Warwick) or a plain castle in an incredibly beautiful surrounding(Leeds).

If you do go to Leeds Castle I wouldn't even bother going inside.

One more thing, regardless of which tour you choose be sure to book either through londontown.com or discount-london, you'll save ten percent, and I think few people realize this because my tour guide didn't even recognize the page I printed from londontown .com

I would pick either Oxford or Warwick or Canterbury, and look, wander, eat, shop, lose yourself in a bookstore. Either of those trips will be too fast to take in anything more lasting than a fleeting impression.

I hate to add to the confusion since I haven't been to Leeds Castle or Canterbury yet, but I really STRONGLY disliked Oxford and Warwick. I thought Warwick Castle reminiscent of Disney World. I LOVED Stratford however and didn't have enough time to explore since we went with Golden Tours who shipped you off an hour or so after leaving the town.
I may get to Leeds Castle or Canterbury next month and can report back.When are you going?
Janis is always a good source of information.

Thanks to all for the info so far. I'm leaving this Thursday the 20th so I don't have much time remaining to decide. I've been looking at booking the day trip with Astral Tours simply because they use mini-vans instead of large coaches. Any feed back on Astral would be appreciated as well.

This decision is difficult because I am very interested in Canterbury & Dover, but am losing interest in Leeds Castle as I continue to research. I am definitely concerned that Warwick might be too "touristy" but from what I'm reading, it sounds like visiting a castle that is too touristy might be a better option than visiting a castle that many say isn't worth going inside for. Lots of posts say it is lovely from the outside and the gardens, but there isn't much to it on the inside. Since I'm going in January, I'm thinking that I will not be able to count on enjoying the gardens as much as I could if I were going in a different season. I guess this is the trouble with an arranged tour but I don't have the time to rent a car and drive around on my own, and I'm trying to efficiently utilizize the time I have available for the day trip outside of the city.

Just to add to your options - take a look at the day trips offered by London Walks (www.walks.com). I was in a similar position last trip when I couldn't rent a car but wanted a day trip - but also wanted to avoid the coach tours that rush you from spot to spot, only stopping for 20 minutes. The London Walks explorer day that we took to the Cotswolds was a great compromise - we took the train then were met by a coach. This gave us far more time out in "the field" and we really were pleasantly surprised.

London Walks does an excellent job for their day trips. I used Frames Rickard when I first started going to London and enjoyed them, but I prefer London walks. I loved Oxford and enjoyed my visits to Stratford and Warwick Castle. I wouldn't classify them as visiting Disney World. These sites are several centuries old and studying English history has always added to my appreciation of each place. I haven't been to the other places yet but they are definitely on the list. One reason why I never tire of travel - so much to see. When you have more time, it is worthwhile going on your own and being able to spend more time to explore. Enjoy your trip.

I also did a day trip with London Walks - Battle and Rye. It was terrific. I did Oxford on my own. The one coach trip I took with a friend did Stonehenge, Salisbury and Bath all in one day - a bit too much. Take a look at what LW is offering.
Enjoy,
Mara

If your trip is this month - the Leeds castle bit will pretty much be a bust. The gardens/ grounds are glorious in the spring/summer but won't be any better than any London park in the winter time.

Don't worry about Warwick being touristy - it gets really mobbed on summer weekends but in the winter it isn't bad at all. Only a small exhibit in the cellars is the least bit schlocky - and most folks skip this part anyway because there is so much more to see. The vast majority of the castle/grounds are really wonderful. Some people think the Edwardian party in the family apartments is "touristy" -- but if you look around at the photos, it is an exact replica of a real weekend party. I think it actually helps visitors visualize how these medieval piles could also work as "modern" family homes.

Most of the advice you've received about other places to go is good, but Warwick/Stratford/Oxford definitely would not disappoint.

Thank you... that is exactly the confirmation I needed to make my decision!