Based on a selection of local cases on the territory of Trieste, the study sheds new light on the ethnic, social and economic structure of individual localities or settlement areas. The aim of this socio-geographical study is to examine in detail, through field research, interviews with local respondents and cartographic representations of the data obtained, the ethnic and social structure of the localities studied and to compare it with their structure of fifty years ago. Comparisons are also made with the state of affairs in 1910. This study provides for the first time more detailed real data on the ethno-linguistic structure of the localities traditionally settled by Slovenes and shows the changes in their social and ethnic structure throughout three key periods: the present post-industrial period, the post-war period of industrialisation (around 1965) and the pre-industrial period (1910). The research also includes an analysis of the changes in land use in rural settings throughout all three periods.