The San Juan convent courtyard exterior was the rear area of a house façade at the Warner Brothers Ranch's suburban street/backlot in Burbank, California. Much of the set no longer exists.
In December 1966, Ronne Troup was cast as Sister Bertrille after Sally Field, the studio's first choice, refused the role. Troup had already begun filming the pilot when she was eventually dismissed after Field reconsidered and agreed to play the lead.
Nuns have been the topic of many film and TV productions over the decades. Some of the concepts in this series are seen in the British TV series Call the Midwife (2012), where change comes to the world and the convent must cope, though so far, none of the Nonnatus House sister midwives has flown...yet.