In a communication type navigation system, a center apparatus receives a present position and destination from an in-vehicle navigation apparatus and thereby calculates a route by searching map data, which is constantly updated. The in-vehicle navigation apparatus receives the calculated route with course information from the center apparatus. When approaching a passing point included in the route, the navigation apparatus displays the course information in the travel direction in superimposition on a forward image around the passing point. The route guide can be thus appropriately performed to follow an actual road state. The above configuration of the system helps prevent problems in costs and workloads resulting from an in-vehicle navigation apparatus holding map data therein.