The B4391 in N.Wales is superb, the B6277
Yes,good one
M-in-T to Alston road even better. A thrash up the Hartside Pass from Melmerby to the summit is great fun. The B6255 Ingleton to Hawes road and continuing on to Thwaite over the Buttertubs Pass is fabulous.
Yes,some of my favourites too in those areas.
Many others also spring to mind but in the company of friends and in a convoy of Z4s they are all sublime. However, if I had to choose just one road to drive then hands down and without hesitation I would head up to Carronbridge just north of Dumfries and then up the A702 Dalveen Pass to Elvanfoot. IMHO the best 15 miles of 'drivers' road in the country. If you catch it right with no or very little traffic and if the weather is dry it is just fantastic :driving:
You can then turn left back down the Mennock Pass and then right at Crawick up to Crawfordjohn. If you look on a map this forms an enormous 44 mile s-shaped route which really takes some beating. In fact it's so good I did it 3 times last summer...in both directions

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