Ok---here is the revised version -- based on some of your comments

Here is a Day 6 comment: If you want to see Beatrix Potter's farm house preserved just the way she left it with many scenes from her books evident in the setting, architecture and furnishings, it is an easy ferry ride across the lake from the Bowness-Windermere dock and about a 20 minute walk on a walking path to Hill Top Farm. I would recommend this over the tourist "Beatrix Potter Experience (or whatever it's called) in Windermere.

http://www.nationaltrust.org.uk/hill-top/

Edit: PS have you seen Miss Potter? Wonderful movie, highly recommend!

Thanks for the tip!

I think your new itinerary is better. I don't think you need a full day to see Conwy. It's not a very big place. You could see another Edward I castle. My favorite was Harlech but that is not close. Beaumarais was also nice on Anglesey. You could also head for the hills.

I think a tour from London to Bath and Stonehenge does not sound at all appealing. Instead of returning directly to London on Day 11, I think you should try to stop at Stonehenge and then ditch the car. You don't need a tour at Stonehenge. It's hard to reach without a car, but you have a car.

Bath could be done as a day trip from London by train. No tour necessary. But you might be able to rearrange, spend one night in Bath, see Stonehenge the next morning (early before the crowds), get rid of car and back to London. If you have to choose bath or Stonehenge, I would choose Stonehenge because you have a car now and you can get there. It is also a truly unique place.

The drive to the Cotswolds will be long. It is a fast paced tour but you are trying to fit a major sites.

For London, check out climbing the dome at St Paul's as an alternative to the London Eye, much cheaper, no lines, and a free easy workout. Other sites to consider in London:
- Changing of the Guard (11:30 on even days I think), followed by lunch at the "Inn the Park" restaurant and cafeteria in the middle of St James Park.
- Cabinate War Rooms
- British Museum
- British Library Treasures Exhibit
- Walk the South Bank (best after dinner)

Windsor is a nice day trip. Add lunch and a walk around the town before heading back to your London hotel

If you don't have Rick's London book, check out Lime Tree hotel. Expensive, but could be worth it. Super convenient location to all the things you're looking to do, very cozy rooms, and they have a killer breakfast.

Henry V’s castle on outskirts of city" - where do you mean? Windsor?, Hampton Court Palace?

We'll certainly not HCP that was still a field when Henry V died. And it's in no way a castle.

Reduce your London stay to 4 nights. Utilise the car while you have it and include Stonehenge+Bath on your driving tour.

Day 5- Tuesday- drive via Hadrians Wall to Keswick - 2 nights
Day 6- Wednesday- visit Lake District
Day 7- Thursday- drive via Conwy Castle to Betws-y-Coed - 2 nights
Day 8- Friday- visit Caernarfon Castle and Snowdonia (rail trip to top of mountain)
Day 9- Saturday- visit Fairy Glen, then drive to Cotswolds - 3 nights
Day 10- Sunday- visit Blenheim Palace and Oxford
Day 10- Monday- visit Cotswolds
Day 11- Tuesday- drive via Stonehenge to Bath - 1 night
Day 12- Wednesday- return car, visit Bath, train to London - 4 nights
Day 13- Thursday- London- visit Westminster Abbey, London Eye, Tower of London

(I would take others advice perhaps and avoid the London Dungeon)

When driving south from Edinburgh, I presume you are using the A1? If so, consider driving through Berwick-upon-Tweed and then back onto A1. After about 20 minutes, turn left and go to the coast at Bamburgh Castle. Then back to A1 for Alnwick.

When you go from the Lake District to North Wales, you will need to get onto the M6 (like an Interstate with 3 lanes each way). Stay on M6 southbound until you reach intersection with M56 - which you take west towards Wales. I would come off the M56 and drive into Chester - although it can be congested. You will need a break from driving & historic Chester would be a good place to have lunch.

From Chester, DO NOT follow the coast road. It is slow going and very uninteresting - the worst bit of the north Wales coast! Take the A55 Expressway & you will get to Conway in about 50 minutes. Whilst in the Conway area, I would take a drive into Llandudno = a Victorian seaside town. I would also visit Bodnant Gardens - just off the A470 going south.http://www.nationaltrust.org.uk/bodnant-garden/

SNOWDON:> Not much point in going if the clouds are down. It costs about £27 for the return train trip. You may have to wait for a slot if you do not pre-book. So, check weather forecasts and make a move at the first 'fine weather' opportunity.

Anglesey has good beaches but Holyhead is a dump. You may like to visit Plas Newydd - which is first left after crossing the A55 bridge. Also consider visiting Caernarfon Castle.

By 'Fairy Glen' - I presume you will stay in Betws-Y-Coed? The road from here to Capel Curig & Beddgelert is VERY scenic. Consider visiting Portmeirion = Italian style village near Portmadog.

On your journey from N. Wales to the Cotswolds, you might like to visit Powis Castle = near Welshpool.http://www.nationaltrust.org.uk/powis-castle/
Stokesay Castle (a fortified Manor House) & the historic border town of Ludlow are also worth a look on such a journey.http://www.english-heritage.org.uk/visit/places/stokesay-castle/

Google the places for more info.

Day 12. I'd ditch the Dungeon and go to Harrods and be able to spend more time at HCP on the 14th