During the start of filming, student protests in Madrid, led to the arrest of director Juan Antonio Bardem, a communist, in the city of Palencia. He was jailed for a few days and released on the condition that he could not talk about his personal life or beliefs during interviews related to the film.
After Bardem's jailing and release, he decided to stop early filming in Palencia, and shot the remaining of the movie in the cities of Logroño (most city scenes, including the main square with the arcades) and Cuenca (most nature shots and the apartment building being constructed). The rest was shot in a Madrid studio.
Voted ninth best Spanish film by professionals and critics in 1996 Spanish cinema centenary.
Official submission of Spain for the 'Best Foreign Language Film' category of the 30th Academy Awards in 1958.