Don't turn up.
That seems to be the view of most of the people I've talked to about the IOI planned excursion to the Black Sea. It apparently involves 4-6 hours on a bus. Each way. Not including the time you spend waiting around at the beginning until everyone gets on the bus. And leaving at 6am. When the time comes, I for one won't be found wanting. I won't be found at all, since I will be sleeping the sleep of the just, or possible just very tired.
Apart from the attempt to inflict long periods of time on buses (which in my case normally consists of periods of boredom interspersed by vomiting), things have been going pretty well here - in fact far smoother than usual. The SA team also did pretty respectably on the first day, and the second day is finishing in a few minutes. I haven't been on any of the excursions so far (being on the scientific committee seems to involve lots of work, but it's all been fun), but I plan to take myself off to the old town tomorrow (hopefully with some other leaders to make it more fun).