I'd like to buy a solid driving map for going from Bath to the Cotswolds and then Oxford. Any suggestions for one that has worked well and is sufficiently detailed but not bulky? Thanks.
Ordnance Survey maps are a solid driving map that have been around forever in hard copy, buy when you get to UK.
They will tell you which roads are 10 feet wide versus 12 feet wide!
When you arrive in the UK - go into a supermarket and you will find road atlases for as little as £3. In the meantime, go on google maps and have a look at the roads - going to street view on likely routes shows you what to expect.
https://www.google.co.uk/maps/@51.6979373,-1.8222234,10.24z/data=!5m1!1e1
When you arrive go into any WH Smiths or petrol station and pick up an atlas. Big format, cheap.
The AA book with more detail is too much detail for what you need.
Ordnance Survey maps are probably too much detail too for driving. Great for walking and finding ancient burial grounds but too much. There are also good folding sheet maps like the Cotswold leisure and touring maps produced by several publishers.
As long as they have the main roads in different colours and you can easily find the attraction symbols you should do fine.
Ordnance Survey are best if you are getting out of the car and walking.
Plillips also do a decent overview. They or AA is probably what I would buy for an overview.
I purchased a good road map on Amazon.com for less than $5.
You can do a mapquest for a particular route.
Rick Steves guide for Great Britain has a great Cotswolds day self driving tour.