The essay starts with a brief overview on the development of documentary architecture photography in Rome from the middle 19th Century to the 1890s. It then highlights the activity of Maria Ponti Pasolini as a both collector and photographer, drawing on her unpublished photographs, diary and letters. The last part of the article reconstructs the circumstances in which one of Italy’s earliest associations for the protection of historical sites, the Associazione artistica fra i cultori di architettura, published the two volumes Architettura minore in Roma, which included a collection of photographs of Rome’s ‘lesser’ historical buildings, with Ponti Pasolini’s crucial contribution.