How about the slope of the terrain ridden? North Georgia has a lot of challenging rolling hills... Rode 5.5 miles today commuting. Lungs are getting better (slower to get winded, but still slow coming back down). There's a moderate yet long hill halfway there that absolutely destroys my legs and leaves me worthless the rest of the trip. You'd really have to ask other cyclists and compare route times. I live in western IL, which is predominantly flat with short, steep hills carved by the Mississippi ages ago. Depending on my route, I can average between 19 (steep 20% hills that wind me) to 23 (almost completely flat). Poor chip seal or road conditions can also make a difference in the average. Overall, average speed is a terrible way to judge your riding abilities. Also, the best way to increase your climbing abilities on that hill is to find a steeper, longer hill and ride it a lot. Then that hill will seem like nothing. So far today: 17 miles on my Bianchi (road bike) and 8 miles of college commuting (fixed gear) planned, probably a ride this afternoon as well.