The role of cities and regions is becoming increasingly crucial in the process of global localization. As vital carriers of urban activities, public spaces are receiving widespread attention; however, the substantial impact of multidimensional experiences of public cultural spaces on urban tourism and the role of cultural identity within these spaces have yet to be extensively studied. This study establishes a framework based on scenescape and stimulus-organism-response theories to explore how external stimuli influence tourists’ behavioral intentions. We developed and conducted a questionnaire survey targeting individuals who have visited the “Most Beautiful Public Cultural Spaces” in Nanjing, China. A total of 287 valid samples were collected for analysis. Four types of external environmental stimuli—physical, activity, mechanism, and virtual spaces—were found to have direct and indirect effects on tourists’ behavioral intentions with cultural identity playing an intermediary role. These new insights provide theoretical enlightenment and practical recommendations for enhancing tourism experiences in public cultural spaces.