October 1987. I lived in Haslemere, Surrey. Had an evening meeting in Mitcham, Started at 8, ended at 10. Clear as a bell when I went in, very thick fog when I came out. Drove very, very cautiously onto the A3 and continued thus. At one stage - I was doing around 10 mph and the fog was so thick I couldn't see any other vehicles either in front of or behind me - I was overtaken by a car doing about 30. Couldn't believe anyone could be that stupid - but someone was. Twenty minutes or so later I came across him again, upside down and on fire. Emergency services were there, Couldn't get past - he had hit the support of the bridge over the A3 and the wrecked vehicle and the ambulances and police cars were blocking the road, so I very cautiously exited the road by going up the joining ramp the wrong way and rejoined the A3 on the far side of the carnage.
It was by no about 11:30 - I should have been home nearly an hour earlier but I decided to stop at an hotel. In those days the A3 went uphill right through Esher and there was an hotel at the top of the hill on the opposite side of teh road. It wasn't until I started to go downhill that I realised that the fog was so thick I had been unable to see the hotel, a large two ro three story building only about 30 yards away.
Kept plugging on, passed Guildford at which point there is a ridge of high ground - the Hog's Back. Over the ridge and as though somebody had thrown a switch, the fog vanished totally. Just as well, because by now my eyes were streaming with the effort of trying to see through the muck. Got home around 2 am expecting Veronica to be frantic with worry - but everyone was fast asleep, blissfully unaware of my adventure (no mobile phone back then)
Mike