Patent ID: 7031829

Claim:
A car navigation system comprising: road map data including node data indicating at least one point of a branch point, a junction point, and an intersection point, and link data indicating a road between the points; a route searching unit for searching for a route between two points based on the road map data; a notifying unit for notifying the route that is searched for as a guide route of the two points; a commanding unit for commanding that the route searching unit select a route as giving priority to an automatic travel road where a vehicle can automatically travel; and a determining unit for determining whether a vehicle where the car navigation system is mounted has an automatic travel guiding device, wherein, when the route searching unit is commanded to select a route as giving priority to the automatic travel road, the route searching unit preferentially selects a route including a road that corresponds to the automatic travel road, wherein, only when the determining unit determines that the vehicle has the automatic travel guiding device, the route searching unit selects a route as giving priority to the automatic travel road.