2 extra days in Scotland

Edinburgh to Bamburgh by public transport will need a bit of planning but it's possible. Train to Berwick then either the bus or book a taxi.

Here's a day tour down into Northumberland which will, I'm pretty sure, pass Bamburgh castle but you'll have to make do with Alnwick.

https://www.rabbies.com/en/england-tours/from-edinburgh/day-tours/alnwick-castle-northumberland-coast-the-borders-day-tour

You could drive to Fort William and take the Jacobite train to Mallaig and back. Beautiful scenery and you'll be the envy of anyone you know who is a Harry Potter fan.

https://westcoastrailways.co.uk/jacobite/steam-train-trip

Hi Allan, we spent 13 days in Scotland in 2018. Without knowing your full itinerary, we loved the Isle of Skye. Do you like castles? Cawdor castle is near Inverness. We drove to Glospie and did Dunrobin castle because they had a falconry demonstration. It’s about 1 hour from Inverness. We loved that too. I would check driving times to John’O Groats. I believe it is a long drive and is really just the jumping off point for the Orkney’s. In other words, not much there.
Here is my Scotland trip report.
https://community.ricksteves.com/travel-forum/trip-reports/trip-report-12-nights-scotland-for-family-of-4

Hi Allan, I did a day trip to John O'Groats and back 2-3 years ago. It was great. I drove up to Wick and then on to John O'Groats. I stopped for lunch in one of the North Sea ports. (Might have been Lybster.) I came back by heading east from John O'Groats past Thurso and down on one of the B roads. It's one of the wee roads. The coast road is a good road, but there were some real curves and hills that I didn't care to repeat in the opposite direction. But I also love a circle route. I wish I could remember where that bit was. I blame my lack of memory on Covid. But the cliffs are wonderful, you can wave to Orkney and drive past Castle Mey. And you can stand at one of those marvelous sign posts that are in the UK in far, far away places.

Tammy, I remember reading your trip report, I'll take a look at it again. Cawdor is on the list for the day we also do Culloden. Thanks for the tip about Dunrobin, that's the direction we want to go. My wife's grandfather came from the Dornoch region so we're going to be heading there as well. Apparently the Dornoch Cathedral is where Madonna was married so she figures that's another good reason to head there.

Pamela, thanks for the info about the drive to John O'Groats, those sign posts are one of the reasons I thought it might make a fun drive since we have the time.

You also go past Dunrobin Castle which for those of us with Sutherland roots is quite interesting. It has a wonderful garden on the North Sea and an interesting museum. Also, just north of Dunrobin is a Broch you can stop off and see very quickly if you've not seen one. And I have decided it was Lybster where I visited the harbor and had lunch. And don't miss Dunnet Head if you go to John O'Groats.

From Edinburgh, it's an easy public bus (or car) ride of 30 - 40 min. to Rosslyn Chapel. The Chapel has/had (when I was there) free guided tours w/ the admission fee. A good day trip if you're a history buff (15th century) or movie buff (DaVinci Code) or appreciate architecture/ renovations of historic buildings or enjoy churches/cathedrals.