AbstractThe relationship between the spatial configuration of the built environment and outdoor physical activity is supported in the literature. However, the role of crime prevention elements and safety is neglected in that relationship. Using structural equation modelling and considering the effect of demographic factors, this study combined concepts of space syntax for analysis of spatial configuration and Crime Prevention through Environmental Design (CPTED) at property and street scales to investigate the direct and indirect relationships between neighbourhoods’ environments and levels of outdoor physical activity. The theoretical purposes have been to measure CPTED elements in two scales and each as a second‐order construct and to gauge pedestrians’ feeling of safety as mediators in the relationship between space syntax measures and physical activity. The results of structural equation modelling suggest that streets’ CPTED elements mediate the relationship between space syntax measures and feelings of safety. The mediation role of feelings of safety in the relationship between CPTED at the street scale and physical activity is also supported. Thus, the study shows that space syntax measures cannot be considered in relation to physical activity without also thinking about its consequent effects on neighbourhoods’ physical environments andalso provides novel insights into the effects of demographic variables on outdoor physical activity.