Ok, I was looking at the map for the marathon again and saw the elevation chart. It looks like it's a gradual uphill the whole way. I couldn't really see the numbers on the side but I'm assuming that it's not a significant elevation change, right? I've trained on rolling hills in a hilly area and uphills at the end of my long runs but I haven't really run a long run where it's uphill the whole way. Clearly it's too late to worry about that now but I guess I just wanted reassurance from people who have done it before that it doesn't feel like 26.2 miles of uphill?