Due to limited space in vertical rental public housing, the role of corridors is vital for public space. Corridors in the context of vertical rental public housing in Indonesia (Rusunawa) have a similar role to alleys in landed housing but with limited access. People carry out diverse domestic and social activities there, including chatting, socializing, sitting, and relaxing. This shows that one setting can accommodate a wide range of activities. The method used in this research is quantitative research through a questionnaire to 114 respondents to identify the relationship between setting, activities, and time. Furthermore, qualitative research is employed through observation, photographs, and in-depth interviews to analyze the system of setting and the system of activity that happens in corridors. This research uses a single study case, Rusunawa Sombo. The results find that Rusunawa Sombo’s corridor has a diverse system of setting and system of activity, ranging from domestic to social activity. This is because it was designed with a fairly wide corridor and aimed to accommodate the community's behavioral patterns as a shared public space. The socio-economic background similarity also creates a strong kinship within the community and eliminates temporal and spatial boundaries in daily interactions. They like to enjoy private activities together and tend to facilitate communal agreements for the use of the corridor as a public space in flexible times. In this way, no one's comfort will be disturbed. Moreover, a wide corridor influences the sustainability and diversity of neighborhood activity and has an important element for domestic, social, and economic activities.