The Kulturerbe4D project aims at making the diversity and change processes of architectural monuments in the urban context virtually visible and experienceable, especially for children and young people, but also for residents and tourists. A virtual city tour providing cultural and historical information is to be combined with the transfer of knowledge about monuments, anthropogenic factors of influence, and protective measures. This article focusses on three main challenges in producing city-scale mobile 4D applications: (a) 4D content creation specifically for historical purposes is highly labour intensive, (b) web applications are better accepted by users but require more adoption to cope with technical limitations, (c) historically accurate 4D content is of disperse visual quality and visualization strategies are rarely empirically proven. Within this article we present our research and development work to overcome those issues.