I think it had been relaid the year before. That road no longer has many heavy vehicles on it. There was a near tragedy 20+ years ago when the brakes failed on a Calor Gas wagon coming down that 25% slope and heavy vehicles were prohibited after that. (Fortunately, the driver managed to drive off the road without hitting other vehicles or the houses down below.)
I could still do with losing 8-12 pounds. I used to try and ride up that hill when I was 5 stone overweight and it almost killed me!
It is
Mytholm Steeps (up Church Lane, from Hebden Bridge).
The trouble with these really steep hills is that the back wheel will often slip if you get out of the saddle, but if you remain seated then the front wheel can lift ... It is a real balancing act, and especially tricky if the road is wet!