Could someone suggest a driving itinerary covering the above areas? I am thinking of spending three days in Bath ( side trip to Salisbury) and would like to spend three or four days in Cornwall and Devon. Any thoughts? Suggestions?

Make sure you do the 'Tower Tour' at Salisbury Cathedral! The stonemason will take you right up into the cathedral roof and spire. It's fascinating! Sorry, that's not much help with your driving itinerary (I don't drive) but I thought it was worth a mention!

Here's a counter-clockwise loop from Bath (but don't miss out on Wells and its marvelous cathedral):

Along the North Devon Coast via Dunster, Lynton, etc - be sure to stop at Clovelly. On to Cornwall and Tintagel and Padstow. I doubt if you'll have time enough to reach the western tip of Cornwall so I suggest dropping down to the Channel Coast to visit the fishing villages of Mevagissy, Fowey, Polperro and E & W Looe. Then head up into Dartmoor Park with stops at Widecombe and Buckland. Exeter's cathedral is beautiful.

I did a 3-day Bristol - Lands End - Bristol driving loop back in May, and it's really quite time consuming. Roads are slow in this part of England.

I went there mostly to drive the roads and not to see the sights (only place I spent some time at is St. Michael's Mount), so it was fine with me. But if you want to do some actual sightseeing, then listen to TuckH.

I'll echo what the others say. Touring/driving/sightseeing in that part of the country are very time consuming. 3 days is not very long to see a lot in the far SW. And especially if you want to explore the amazing Dartmoor, I don't think you'll have time enough to go much beyond Wadebridge on the north/Plymouth on the south.

I LOVE south Devon and Dartmoor so if it were me and I only had 3 or 4 days I wouldn't try to get too far into Cornwall.

Now - if you cut one day from Bath and had 5 days for Devon/Cornwall you be able to see a lot more.

But you left out a very important detail - when is this trip? It can make a huge difference. For instance a drive that normally takes an hour or two might take 4 or 5 on a bank holiday or school holiday weekend. And in winter, with the early darkness - the narrow/single track roads are harder to navigate.

I congratulate you on attempting to drive in Cornwall!
We took the train from Exeter to Fowey and made that our base because it is so beautiful. From there we visited The Lost Gardens of Helligan & The Eden Project. Lost Gardens trip was by boat then bus. Those roads are extremely narrow and you will not be able to build up speed.
I agree with janisj - cut a day ( or two) from Bath. We were able to see the Roman baths and take an open top bus around Bath all in a day trip from London. Do have lunch in the Pump Room at the baths - absolutely wonderful. We walked in around 1.30 and were able to get a table but they do close around 2.30 for lunch but carry on serving teas.
Have a wonderful time!

Hotticket - What do you enjoy doing because this may have some influence on how many days you spend in each area and also where you go?

For example if you love the coast then Tuck H's suggestions are perfect. If you like country walks then Dartmoor and Exmoor in Devon are thrilling (albeit not much fun in the depths of winter). If you like gardens then don't miss the Lost Gardens of Heligan, Lanhydrock and even the overtouristy Eden Project in Cornwall. If history is your thing then you can't neglect Plymouth and Tintagel.

Agree with Janis that if you can amend your itinerary to have 5 days for Devon and Cornwall this would be more profitable. You can comfortably do Bath and Salisbury in 2 days.

You could also help on fatigue by choosing say one location for Devon and Cornwall and doing day trips. Somewhere like Thurlestone or Salcombe in South Devon would give you access to East Cornwall, South Devon and Exeter.

Thanks, All.
TO answer some questions: I am going in June. I prefer the coast, history , and gardens. I do not care about walks in the country.

I love the idea of staying in one place and taking day trips to both Cornwall and Devon. Thanks for the suggested stops,londonengland. I will also cut the time in Bath to two days.

Any other thoughts are welcome and appreciated.

First of all, If you like gardens, Stourhead is between Bath and Salisbury. It is probably the premier example of the English garden style.

We stayed in St Ives in Cornwall and went to the more southerly Cornish gardens. It's probably out of your range but Trebah (south of Falmouth) is the most beautiful garden I've seen. And it seemed better kept than the National Trust gardens.

Also, for walking, there's a path along the Cornish coast. Don't know how this would work out for drop-in, drop-out walking.

Why not rent a National Trust cottage on the coast in north Cornwall and make day trips from there? You could go up into Devon, down along the gorgeous north Cornish coast and visit the lovely gardens at Lanydrock. Ten years ago we spent a blissful week at Doyden, near Port Isaac, right on the Atlantic cliffs, and are going back again next summer.