Good idea or bad idea

I am not sure if it is a good idea or a bad idea, but this week I decided to do the Great Wall Marathon the weekend of May 17th. A group of friends are going to do it and someone dropped out so I am taking her spot. The smart thing would be to do the 1/2 marathon (13.1 miles) but since most my friends are going the full my pride is sort of pushing me to do the full. I have already done four 1/2 marathons and doing a full has always been something I want to do, so why not start with one of the hardest? The terrain will be a bit rough (the understatement on the century) with it being on the wall, but how amazing it will be to do it. The whole race is not on the wall, but I will hit the wall twice. When not on the wall, I will be running through villages and rice fields among other things. While I think (well, know) that I will be hurting when I finish, I also know that this may be one of the coolest things I have ever done. I have the next week off of school and decided before doing the marathon not to travel, so now my holiday will be spent trying to run and do stairs. Today I started my training with an hour and twenty minute run followed by going up and down the twenty flights of stairs in my apartment building. If anything, I will be an expert stair climber by the end of this. I will update how I do after the race and give a report of how my body survived it. One thing I know for sure, if I did not go for it I would regret it when I leave China, so I have to do it.