In traffic I usually average 20kmh / 12mph because of the stop and go and when I ride to the frame shop I can average 30kmh / 19mph but then I have 10km to get out of the city on nice routes and then have 40 km of open road where there are no stops save for my coffee break in the middle.

The long commute usually takes 2 hours one way and I am usually carrying some gear as I often sleep over and ride back the next day.