The Tuscon Marathon has a fast course. It starts out in this little desert town and you run to Tucson. It is a perfect down slope for 20-22 miles and then flattens out. I remember only 1 little hill on the whole course. I did have a little problem with the low humidity in Arizona , I was really thristy during the run. The race needs to iron out some problems they had at the start and finish . They did say they would fix these problems this year. A good race.