A few years ago I used to cycle from Sawston to Cambridge, which google maps tells me is 8.5 miles and took me 40 minutes. I always meant to get faster but I was too lazy to. I don't move anywhere with that length of commute in the future (not so much for the annoyance job-wise, but for getting back into Cambridge for evening activities). Although I know plenty of people think nothing of 40 minutes travel.