I have several "go to" loops that begin and end at my door. I can't tell you how long they are, or even my average speed. I chose them for the convenient access, variations in terrain and views, and time-to-ride. I have a 1/2 hour ride that my wife and I do frequently at pace for a workout. There's a 45-minute loop that has some substantial climbing in it. And then there is a 1 hour ride with climbing and some straight fairly traffic free stretches in it. It's pretty to add a 30-minute out-and-back along one roadway if I feel like it.
Of course, there are other variations that can be added or subtracted. I don't have that much time to be on a bike, so must fit in small blocks of time for it. Works out okay for now. After retirement, I expect to explore the Texas hill country more freely.