A distinct feature of Muslim cities is demarcated separation between zones of public economic and private domestic activities. Such spatial distinction has been the organic extension of a social structure with limited presence of women in public zones. However, separation of spaces in the Muslim city and the way it is utilized, shaped and reproduced by men and women is not a simple case of dividing public-private geographies and assigning them to males and females, respectively, and has been subject to appropriations and adaptations. The Shiite traditional Muharram procession is one of the instances of such appropriation which produces a semi-private or tertiary (social and spatial) realm, where gendered behaviours are more fluid, the loyalties of the kin stretch beyond the dominant normative, and both men and women move with greater ease. Such spatial fluidity exacerbated during the rituals of Muharram, where presence of women in public space is promoted and invigorated. Among other means, the ephemeral space sanctification is utilized to create a space where the social sanctions are temporarily lifted, and gender spatial boundaries are suspended. As an ethnographical piece of research using methods informed by urban planning and urban sociology and based on a cross-disciplinary study of gendered spatial divisions (socially and architecturally), this article endeavours to investigate the notion of ephemeral space sanctification in a Muslim city among the Guilani population in Lahijan, in northern Iran.