TdF Stage 12 tomorrow features L'Alpe d'Huez (avg. 8% gradient maxing out at 13%) where you can bet, despite these competitors being the premier riders on Earth, that avg mph will be considerably lower at times than some of the averages posted here... Stage 11 today had some amazingly steep climbs--e.g., a single rider on a breakaway was getting pretty close to the finish where one of the commentators estimated he'd be in about 25 minutes, which seemed to work out to about 6 mph. Interestingly, there was a point in the Stage 10 coverage at about 98 kilometers from the finish when Phil Liggett casually observed that the peloton was going at a 6.8 to 7.4 mph pace just as the camera swept by I think a homemade road sign saying it was a 13% incline. On the Stage today, the guys were hammering going downhill which is pretty easy to do and obviously an effective way to increase the avg. mph of a ride.