13 nights in England-Scotland

I liked both Oxford and Cambridge, but your time is short and I think you'd do better to choose one of them. Oxford and Bath are both rather close to the Cotswolds, though on different sides. I haven't ever rented a car in Europe so we need for someone experienced to weigh in, but I think it would be possible to pick one spot sort of in the middle of that area and hit all three of those places without changing hotels. Mind you, parking could be a challenge in both Oxford and Bath, but I think with proper planning (maybe a Park-and-Ride outside Oxford?) you can solve the problem. And avoiding a hotel change is always a good thing.

There is extremely rapid rail service London-York-Edinburgh. Starting over by the Cotswolds certainly changes things, but I think you might do well to drop the car in York if not before and complete the rest of the trip by train.

You can look at rail schedules and fares for early June on the National Rail website. If you're going to take any substantial train trips, you'll want to get your travel times locked down pretty quickly so you can buy Advance tickets when they become available. They will be vastly cheaper than regular tickets bought later. But Advance tickets are non-refundable and exchangeable only at a fee (plus you pay the difference in fare); you need to be sure of your timing before purchasing.

Compare the rail times to driving times on ViaMichelin.com.

I understand the desire to have a car for the flexibility to make stops along the way, but the fact is that you have too many destinations and too few days. You don't have time to stop along the way (in my opinion). For example, 3 nights in Edinburgh means two full days there and a few hours on the day you arrive from York. You plan to spend one of those days in the Highlands.

You might seek opinions on the best use of that one day outside Edinburgh. I know the Rabbies tours get really good reviews, but I remember reading a comment elsewhere that the company's Highlands tour spent most of the time on the road, so clients had very little time off the bus. And that is a really good tour company; I have no reason to think other companies' "Highlands in One Day" tours would be better. Three nights for "Scotland" is just not adequate, no matter how you divvy it up.

If your boys are Harry Potter fans, they will want to see Durham cathedral. You could spend a night there instead of Cambridge. It will probably cost more than renting a car, but I would take trains from London to York to Durham to Edinburgh and do a Rabbies Day tour of the highlands. If you have not driven a car in the UK before, it can be stressful. Maybe rent car outside London for Cotswolds segment, return outside London and take trains for rest of itinerary.

Thanks to you both! Maybe we should stick with 6 nights in London (and do day trips to Oxford and Stonehenge), 2 nights in York, and 5 nights in Scotland (divided between Edinburgh and another town?)...and travel by train between cities. OR we leave out Scotland for another trip and focus on England...not easy to decide!

I think a fast pace may not leave you a lot of time for experiencing the outdoors, which is something much enjoyed in the UK (assuming you have weather-suitable clothing). I'm one who always votes for itineraries that cover less ground. I'm making what must be my 8th or 10th trip to Great Britain this year (I've lost track), and it will be the first time I've gotten up to Scotland. There's still much I haven't seen in England and Wales.

We rented a car for 28 days in our self drive tour of S. Wales and England in 2017. It was great, but driving has its challenges. You simply must have a GPS or Nav system on the vehicle. Driving in the cities, traffic can be terrible. Traffic in the North of England is a lot better than around London.

Cambridge, I suggest doing a day trip. Parking is an issue and driving anywhere near London is a royal pain.

Oxford is nice, you need a full day and another day to just do the Rick Steves self drive of the Cotswolds. Rent a car from Oxford for the day to the Cotswolds. You are missing Stratford Upon Avon, which is a wonderful city to visit, especially if you love Shakespeare.
Consider skipping Oxford and visiting Stratford Upon Avon. Also, you kids might enjoy Warwick Castle. Warwick is NW of Oxford.

York is one of my favorites in the UK. We did 3 nights there. Loved the Minster, walking the ancient walls and the National Railway Museum. There are some very nice museums there and a great district with the narrow streets and market stalls.

As for driving through Durham on your way to Scotland, I don't recommend that unless you plan to visit Durham. You could see it in a day and spend the night there. If you don't plan on visiting, just driving through will be more frustrating. The Cathedral and its area are great, but you won't see much of it from the thru highway.

Thank you all for your comments and suggestions! Will definitely take them into consideration...