A navigation system comprises a navigation apparatus mounted on a vehicle
and a portable information device communicable with the navigation
apparatus based on a predetermined communication protocol. The navigation
apparatus searches a route from a current position to a destination, and
guides the searched route to the vehicle, that is, crews on board. The
navigation apparatus further comprises a unit for searching a further
route from a further current position to the destination in response to a
predetermined command. The further current position is a position at which
the unit searches the further route. The navigation apparatus further
comprises a transfer unit for transferring information indicative of the
further route to the portable information device. This device provides a
person, who carries the device, with a further route guide by showing the
further route, after the route guide performed by the navigation
apparatus.
