Not centuries but eventful years must be The Forsyte Saga. I am sure many grans remember the superb BBC production with Eric Porter, Kenneth Moore, Nyree Dawn Porter, Susan Hampshire et al. They even changed the times of evensong in some churches so that it didn't clash with the new episode each Sunday evening and I remember great excitement among the younger members of my school when I was on lunch duty following the episode where Soames Forsyte raped Irene. It's unlikely ever to be a re-run because it was filmed in black and white.