Abstract: On receipt of route information, map data in an area near the route is read S11. One intersection existing on the route is extracted from the read map data, and intersection-connected links connected to the intersection are extracted S12. The road widths from the center line to the right and left sides are specified for the intersection-connected links based on attribute data such as the actual road width of the intersection-connected links S13. New lines are drawn for all the intersection-connected links by translating the line representing the intersection-connected link as the center line rightward and leftward by the specified road widths, to determine right and left side lines of the intersection-connected link S14.

Abstract: A path search part searches for an optimal guidance path between any two locations arbitrarily designated on map data. A lane guidance information generation part divides the path searched in the path search part at intersections into a plurality of between-intersection roads. The lane guidance information generation part then generates lane guidance information by referring to the map data corresponding to each of the between-intersection roads. Herein, exit lanes of the between-intersection roads are each restricted by heading direction control written on the map data. If the exit lane corresponding to the next between-intersection are found plural, the lane guidance information generation part further refers to another between-intersection road located next. In this manner, it becomes possible to provide the lane guidance information with consideration for not only the closest intersection but some more intersections ahead.