"Summertime" was an adaptation of the Broadway play "The Time of the Cuckoo" by Arthur Laurents. The stage production starred Shirley Booth and opened on Oct. 15, 1952 at the Empire Theatre in New York and ran for 263 performances.
Katharine Hepburn's apartment is actually an amalgam of three different locations. The door through which she enters the apartment belongs to the Trattoria Sempione, a restaurant that still exists today. Her bedroom belongs to an apartment two miles away in the suburb of Dursoduro, and the terrace was a purpose-built set in Compo San Vio.
Director David Lean said filming on location in Italy was expensive because he had to pay local merchants whose customers were scared off by the camera equipment and crew.
In the french-dubbed version, known as "Vacances à Venise" - released in October 1955, Katharine Hepburn is dubbed by Jacqueline Porel, Isa Miranda by Lita Recio, Darren McGavin by Jean-Claude Michel, Mari Aldon by Claude Winter, Jane Rose by Denise Grey, Mc Donald Parkeby Jean Toulout and Andre Morell by Roger Tréville. Rossano Brazzi dubbed himself as he was fluent in French.
Reportedly David Lean's personal favorite of his own films.
The number of tourists traveling to Venice doubled after the film's release.
The story was also later adapted as a Broadway musical called "Do I Hear A Waltz" by Arthur Laurents with songs by Richard Rodgers and Stephen Sondheim. The show opened at the 46th Street Theatre on March 18th, 1965 and ran for 220 performances. Laurents later revised the script and a new production was staged in 2000 at the Pasadena Playhouse in New Jersey. Recordings of both productions are available for purchase on specialist websites.
When Katharine Hepburn filmed the scene where she falls into the canal, one of her eyes became infected. That infection stayed with her the rest of her life.