Personal indoor navigation systems guide users through buildings by taking into account several parameters such as the general topology of the building, the walking time to the next destination or the accessibility of certain rooms. Displaying navigation instructions on mobile terminals raises several problems with respect to the needed positioning system on the one hand and integration into the providers premises on the other hand. Another possibility is to utilize existing infrastructure and provide a personal navigation service by means of a distributed stationary display system. Such systems are already available with hundreds or thousands of displays per site, e.g. at hospitals, airports, campuses or other major corporations. This paper presents a new approach for calculating and visualizing indoor navigation instructions for such systems. Based on a both geometric and graph-related building model an overlay graph is created, which allows the generation of coherent and intelligible navigation messages and graphic representations. Also landmarks are utilized to increase the comprehensibility for the user. Finally, a feasibility study conducted with a prototype implementation at Munich Airport is presented.