There are persistent rumors of a missing episode, which existed only in a rough-cut form, about a blackout in the hotel. This has been emphatically denied by cast, crew and writers however, and there is no supportive BBC documentation for filming/recording dates.
Basil and Sybil Fawlty were based on Donald and Beatrice Sinclair, genuine hoteliers who ran the Gleneagles Hotel in Torquay where John Cleese stayed whilst filming on location in early May 1970 with the Monty Python team. Mr Sinclair's irascible antics included: berating Terry Gilliam for eating his meals in "too American" a way; throwing Eric Idle's briefcase over a wall because of a "bomb scare" (the scare was that Idle left the briefcase in the reception area); disbelief at Michael Palin asking to pre-book the Gleneagles TV to catch a show; after Graham Chapman requested an omelet made with three eggs, Sinclair brought him an omelet with three fried eggs perched on top. When asked by Cleese to call for a taxi, he argued with Cleese and took his time calling for the cab. Mrs Sinclair later complained that the sit-com had been unfair to her husband, and she described John Cleese as an "utter fool" who had "made millions out of our unhappiness". The Gleneagles Hotel, under new ownership, now runs Fawlty Towers weekends once a month where guests are looked after by actors who play the part of Basil, Sybil and Manuel.
The building used for the exterior shots, on the grounds of Buckinghamshire's Wooburn Grange Country Club, was severely damaged by a fire in March of 1991. The building was subsequently demolished and 8 homes were later built on the grounds.
The recording of the final episode ("Basil the Rat") was postponed due to a BBC strike, and so was not broadcast until October 1979, six months after the rest of the series.
During the original run of the series, Richard Ingrams - then editor of "Private Eye" - wrote a scathing review of the programme. John Cleese had known Ingrams for many years and was also a friend of the magazine's proprietor, Peter Cook, and so took great exception to the review. Cleese's revenge was to write in a character called Mr Ingrams into a later episode, a guest whom Basil discovers blowing up an inflatable sex doll.
As the series progressed, each episode's opening shot of the Fawlty Towers hotel sign shows rearranged and misplaced letters. Variations include: Watery Fowls (with a kid seen adjusting it), Farty Tower, Flay Otters, Fatty Owls, Warty Towels, Flowery Twats and Farty Towels.
Andrew Sachs is German by birth and was asked to dub his own lines into German when the series was exported. Being a native German speaker he had no problem with the script, but it took him quite a while to work out how to speak German with a Spanish accent.
Andrew Sachs (Manuel) was paid damages by the BBC after a jacket was treated with acid by the special effects department to look as if it was on fire. It really did burn through to his skin and he still bears the scars.
John Cleese (Basil) nearly knocked Andrew Sachs (Manuel) out with a heavy saucepan when the actor made an unexpected move during filming after five days of rehearsals. The hapless actor had a headache for two days.
John Cleese (Basil Fawlty) and Connie Booth (Polly Sherman) were really husband and wife when they created and wrote the scripts for the first series. By the beginning of filming for the second season their marriage had fallen apart and they had divorced.
John Cleese wrote a forerunner to "Fawlty Towers" in Doctor at Large: No Ill Feeling!, featuring a badly-run hotel and its brusque, henpecked owner. Producer Humphrey Barclay suggested to the writer that a series could be spun out of the premise.
John Cleese says in his DVD commentary that Prunella Scales was so unlike the character she played, the harpy Sybil Fawlty, that they had trouble getting the tenderhearted Scales to hit Basil or any other character who incurred Sybil's displeasure hard enough to make it look realistic and were constantly having to do retakes of her scenes.