Carnforth station was chosen partly because it was so far from the South East of England that it would receive sufficient warning of an air-raid attack that there would be time to turn out the filming lights to comply with wartime blackout restrictions.
On initial release, the film was banned by the strict censorship board in Ireland on the grounds that it portrayed an adulterer in a sympathetic light.
The screenplay was adapted and based on Noel Coward's 1935 short one-act (half-hour) stage play "Still Life". It was expanded from five short scenes in a train station (the refreshment tea room of Milford Junction Station) to include action in other settings (Laura's house, the apartment of the Dr.Harvey's friend, restaurants, parks, train compartments, shops, a car, a boating lake and at the cinema),
This movie was David Lean's first Oscar nomination as director.
According to several Billy Wilder biographies, the scene in this film where Alec tries to use a friend's apartment in order to be alone with Laura inspired Wilder to write The Apartment (1960).
Laura borrows books from the Boots Lending Library. Such Lending Libraries were an offshoot of Boots Pharmacies. Boots is a major pharmacy chain in the UK. It was founded in 1849 and still exists, although in a much different, more diversified form. The Lending Libraries were started in 1898.
Laura borrows books by Kate O'Brien. Kate O'Brien (1897 - 1974), was an Irish novelist and playwright.
The two films that Laura and Alec choose between, 'The Loves of Cardinal Richelieu' and 'Love in the Mist', are fictional.
The film trailer they see is for 'Flames of Passion', a fictional film, supposedly based on a novel, 'Gentle Summer' by Alice Porter Stoughey, both fictional.
The poem that Fred asks Laura's assistance with is by John Keats, "When I Have Fears That I May Cease to Be", the actual quote being 'When I behold, upon the night's starr'd face, Huge cloudy symbols of a high Romance ....'.