Another slide from the archives – this was taken in 1982 at the top of the Honister Pass in the English Lake District. The warning presumably related to the 1-in-4 /25% descent that would follow.
The sign has long gone, as presumably it fell victim to the standardisation of road signs.
On the same trip, I can remember driving over Hardknott Pass which was far more worrying. I had an old Ford Escort which needed a fair bit of time to warm up before it could be relied upon to tackle anything steep, but I was starting the climb from Eskdale Youth Hostel which isn’t far from the base of the pass so didn’t give much opportunity for the engine to warm up. I managed to chug slowly up the pass (which is more like 1 in 3 than 1 in 4). I stopped at the top to admire the view, then on the way down I was rather un-nerved by the fact that the road was descending so steeply that I couldn’t actually see any road beyond the car bonnet (that’s the “hood” for American readers) … so it felt like I was driving on thin air.