Frequency: Every weekday evening, with a repeat the following afternoon and an hour-long omnibus edition on Sunday mornings.
Audience: 3.75 million a week.
Formula: Started as an agricultural version of the popular detective serial Dick Barton. The subtitle, 'An everyday story of country folk', has been quietly dropped, as has the heavy top- dressing of farming propaganda. These days, it's 15 minutes of domestic drama.
Rivals: Few. Mrs Dale's Diary once posed some threat, but since then The Archers has seen off both Waggoners' Walk and Citizens to become the world's longest-running drama series.
Creator: Godfrey Baseley, still a regular listener. He will be 90 in October.
Where is Ambridge, then? Baseley imagined it to be the Warwickshire town of Alcester, where he grew up. The Eddie Grundy Fan Club meets in The Bull at Inkberrow, which is often used for photographs, but real addicts pinpoint it more accurately: just off the B3980, six miles south of Borchester, 17 miles west of Felpersham, in the county of Borsetshire.
Theme tune: Baseley took several bits of music home and played them all weekend. By Sunday night, the only one he could still bear was 'Barwick Green' by Arthur Wood. The jaunty tune signifies supper-time, children's bathtime, sherry-time all over the land. After particularly grave episodes, the stronger middle section is played. When things are really dire, shows have been known to end in silence.
What dire things? The most recent was the death in a car accident of the solicitor Mark Hebden.
Any other sudden deaths? Yes, Polly Perks also died in a car crash. Most famously, Grace, Phil Archer's first wife, died in a fire at the stables. This occurred in 1955, on the first night commercial television was broadcast. Twenty million listened. The timing was no accident.
Who listens to it? Among others, Cliff Richard, Barry Norman, Phil Cool and the wives currently residing at Nos 10 and 11 Downing St. It is said that the Queen once confessed to being hooked. As is her mother.
Any other royal connections? For the 10,000th edition, Princess Margaret and the Duke of Westminster performed on the show, on behalf of the NSPCC.
Have other 'real' people appeared? Terry Wogan featured briefly, as did John Peel and Anneka Rice. Britt Ekland made Eddie Grundy's day when he visited her panto dressing- room, and the otherwise mute Prue Forrest was given a celebrity voice, just once, by an ultra-rural Judi Dench.
Offspring: Former Archers editor Liz Rigby set up a Russian 15-minute daily soap called House 7, Entrance 4 for the World Service: it is already attracting even larger audiences than its parent.
Does pre-recording mean it's hopelessly out of synch with real life? Not always, though there's a tendency to get the weather wrong and complain about too much rain when a national drought has been declared. A special episode was hastily added when troops were mobilised in the Gulf War.
Anything that makes you want to kick the set in? Episodes devoted to the tiresome, imprisoned Ambridge One, Susan Carter; alarming hints that the glorious lush Julia Pargetter might be drying out.
The bottom line: is it any good? Yes, it's wonderful. A particularly good writing team is currently coinciding with some splendid actors. To discuss an episode with fellow addicts is to enjoy the satisfaction of a good gossip, without the misgivings attendant on real calumny or detraction.