My father, who will be 70 this year, recently moved to the west coast of Canada where the winters are milder and where he has been able to get out on his bicycle more often, despite the fact that this year has apparently been the rainiest winter and spring in a long time.
So far this year he has ridden 834 km which is 20 km more than he did all last year ... and it isn't even summer there yet! Not bad! And he is often out for 50+ km rides.
I hope I'm doing that much (or more!) when I'm his age.