One group I ride with is mostly older riders. They split up into two groups: the Turbos and the Turtles. Sometimes the Turtles will start a half hour earlier or the Turbos will take a hillier route. There are times when they do completely different rides on the same day.

I lead some Wednesday evening rides which have 2 or 3 different length routes. The idea is that we all start at the same time and end at about the same time so we can go eat dinner together. The ride leader goes with any new riders if they are unsure of how fast they can go.