To shorten the time required for route calculation when a user specifies a destination to search a route.

When an electric power source is fed to a navigation system, and when the present position is started to be detected, the route using as the final point a prestored memory point and a point set as the destination in the past and using the present position as the start point is calculated to store the calculated route in a storage part. When the user sets as the destination the point set as the prestored memory point and the point set as the destination in the past (step S200), the already calculated route using as the final point the destination set by the user is read out from the storage part, and the read-out route is used for a route guide. Processing for the route calculation is thereby omitted when the user sets the destination, and the time required for the route calculation is shortened thereby as a result thereof.