I vaguely remember watching a British TV show (possibly only one show, but maybe a series), where nuclear war has occurred. A family (maybe in Wales) has survived because they live in a remote valley, where the explosion/fallout missed them because the valley was steep sided.
I think the premise was that the family couldn't leave the valley due to, what they thought was, the radioactive fallout elsewhere. The final part of the show was one of the characters walking out the valley.
(I only remember this because there was a scene where one of the main female characters was nude in the bath, and showed breasts (I was about 7 or 8 at the time, hence why I remember it)).
I want to say there was an actress in it called something like Pippa Hinchley.