I've read a lot of threads but i'm still a little confused. I'm flying into cuzco at 9am on a Wednesday. I'm probably going to spend the night there and take the train to MP on Thursday. I've read in some places that tickets sell out but i've also read that I can buy tickets beforehand? so if i buy tickets beforehand, i can go to MP the same day? or would it be better to find something else to do on Thursday and go up to MP on Friday? If i go up on Friday, would it be a bad idea to take the train back to Cuzco that evening? or should i just stay the second night?