We present a GIS-based system and its algorithmic features in the context of a real-time public transportation problem. In this setting, a rider who would like to use the public transportation system calls an information line for the nearest bus stop and the available routes. The system we have developed finds the shortest path together with the walking directions from the rider's current location to a nearest eligible bus stop and from the last bus stop to the rider's destination. We use Esri's NetEngine software to solve this shortest path problem and generate walking directions.