The only place I can think of like that near you is Winter Hill?
I had never noticed on the OS map that there is a road up there, but obviously those big transmitters need to be built and maintained so there have to be access roads.
I was trying to work out what road you were talking about. I found one which looks promising on Street View only to find this halfway up where the SV coverage finishes...
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Which makes it seem like you were a bit naughty going up there...
But then I found this video, made 11 years after the SV car did the climb...
There were lots of people up there including motorists and cyclists. And look at the sign then...
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It looks like the sign had been covered with white plastic, which had then got partly ripped off by the wind? Have access rights changed up there?
The last 200 ft of ascent didn't look possible. At 1,350 ft I could have sworn that Simon Warren was almost at the summit, but sure enough, the road kept grinding up. I suppose that is what huge objects like that mast do - they are still quite a long way off but look closer because of their size.
The OS map has the top at 456 m, which is '
only' 1,496 ft but Simon's GPS also gave a figure of around 1,550 ft. I would rather trust OS than the GPS though. GPS altitude is usually out by up to 2-3% in my experience.
I too would be
VERY careful descending that road! Adult pedestrians wandering about with children and dogs, probably sheep, some cars, other cyclists, potentially horse riders, potholes, gravel, cattle grids...
All in all though... I might cycle over some time to ride up it!
PS I found warnings online of the dangers of being at the top of Winter Hill in winter! Icicles potentially falling down on you from support cables hundreds of feet above your head!