Roads over 400m are fairly plentiful in North England and in Wales, but after that, it starts to get fairly thin and airy in the UK. The highest ‘Col’ is in Scotland, Cairnwell Pass, Aviemore which rises to 670m (2,198ft) over 8.1kms. Scotland also has some much higher roads which aren’t Col’s or passes. The road up to the radar station at Lowther Hill at 725m (2,379ft) being the highest, but you have to come back the way you came up. Surprisingly though, this isn’t the highest paved climb in the UK. That accolade goes to a fairly unknown climb in Cumbria (although it’s gained a lot of airtime in the last 2 years) The ‘Big Friendly Giant’, situated in the Pennines, inland from the Lake District, is Great Dunn Fell (GDF). An access road to a radar station, like Lowther, which rises from the small village of Knock to an almost staggering altitude for the UK of 848 m (2,782ft) That’s 123m higher than anything else and it gets to that summit via a perfect strip of tarmac which averages 8% over the main 7.4km route and rises over 630m vertically from start to finish.
Strava classifies GDF as a category 2 climb. Although tackling its slopes via Long Marton achieves category 1 status 707m of verticle ascent over an extended 11.3km climb. Faintly ridiculous when you consider that’s nearly as much climbing as the total height of Lowther! Oh, and just for perspective, Box Hill has 128m of verticle on the most basic version of the Strava segment (I know there are longer Box Hill segments but really… it doesn’t add more than 20m).