BackgroundThis study explores which architectural features of interstitial spaces improve visitors’ interactions with the overall museum space and with other visitors at the National Museum of the Islamic Revolution and Holy Defense in Tehran, Iran. Interstitial or liminal spaces are defined as “in‐between” spaces connecting primary spaces in a building that have a key role in relating humans to places.ObjectivesThis study asks which geometric features can increase the socio‐emotional interactions for visitors.MethodsTo answer the question, observations of behavior and body language were made at the study site. These data were analyzed based on body language science and neuroscience literature. Five in‐between spaces connecting exhibition halls were selected, and visitor behaviors were observed and analyzed using the Observer XT software by Noldus.ResultsResults showed that certain types of passages were associated with the highest levels of emotional interaction, while others are associated with the highest levels of social interaction.ConclusionsThe results of this study align with earlier neuroscience findings regarding brain activities in relation to certain geometries. The methods used in this study can be applied by architects and designers in their predesign planning and post design evaluation processes to improve socio‐emotional interactions for visitors.