Easy answer to this question. 11. Eleven. Total attendence.
Well, I might just win this one. Not the total attendance but the Chelsea attendance.
In 2000 or maybe 2001 (though could be '99 or '02, who knows?) we played Vicenza away in a pre-season friendly. There were a total of 8 of us in the Chelsea section; Myself, my wife, a family of four and a bloke and his girlfriend. Now I'm pretty sure that the girfriend wasn't a Chelsea fan and nor was the wife in the family. My wife's a little iffy on this too. Although she follows them 'cos I do I'm not sure I could call her a real supporter given that she's from Huddersfield and supported United as a kid (hope she never reads this 'cos she hates me saying that). In some ways then there were 5 of us 'proper Chelsea', the father and his kids (both under ten), me and the other bloke.
Anyway, it was an evening kick off and after a superb meal in the town's piazza we found ourselves on this open terrace where, within a minute of kick off, a massive thunderstorm began and I experienced the heaviest rain I've ever seen at a football match. I decided to ignore it and show the locals (good turnout from them btw) that us Chelsea fans don't mind a bit of rain so I stood out there on my own (everyone else had retreated inside the tunnel that led to the terrace) while belting out a few 'carefrees' and some chosuses of 'Chelsea, Chelsea, Chelsea'. Eventually my wife, the dad and his kids joined me, the kids finding the whole thing hilarious, as did the locals as a matter of fact. Got some very bemused looks from them, most of whom seemed to have known the weather report and brought umbrellas. The rain was ridiculous, so heavy I can't really describe it. I wasn't at the Bristol City match that some talk about but I was at Oxford (1-1 mid-late Eighties) when others say it was the wettest they'd ever been at a match (it was mine too until this game) but believe me this was rain of biblical proportions and WAY worse than Oxford.
Not claiming any special kudos for this, just so happened we were on holiday there at the time, I don't make a habit of doing pre-season friendlies abroad. We were staying in Venice and took a train back after the match. The air-con was stuck full on (it being summer) and we nearly got hypothermia, both of us shivering away for the entire journey which took ages as this late night train kept stopping in the middle of nowhere. It was more uncomfortable than coming back from some God-forsaken place up north on a special when the windows had been put in. Didn't warm up until we got back to the heat and humidity of the Venetian night. It was a very funny match and experience, one I'll always remember though I can't remember the score (but pretty sure we lost). I think the rain washed away that part of my memory.
There was a write-up in the next 'Chelsea' magazine from a journo in the main stand which mentioned the family and I was a bit miffed that I was missed since I was the first one out there and 'stood my ground' the whole match. Not sure if we should count the journo as a fan or not but that still only makes 9 in total. I looked for others but couldn't see any, can't swear there weren't though. Either way a very small Chelsea attendance.