Patent ID: 7363146

Claim:
A car navigation system provided in a vehicle, the system comprising: a current position designating unit configured to designate a current position of the vehicle; a route guiding unit configured to indicate a guiding route to a destination; a disk reproducing unit that is able to read and reproduce data from one of (i) a first disk storing map data covering a predetermined map range including the guiding route to the destination and (ii) a second disk storing data other than the map data, wherein the first disk and the second disk are interchangeable in the disk reproducing unit; a storing unit that stores a portion of the map data partially read out from the first disk via the disk reproducing unit based on the current position, the portion of the map data corresponding to a given partial range included in the predetermined map range, the given partial range not including the destination while covering a partial route included within the guiding route up to a peripheral boundary of the given partial range without reaching the destination; and a controlling unit configured to cause a display unit to display a map based on map data read out from the first disk when the first disk is reproduced by the disk reproducing unit or based on the portion of the map data, which is corresponding to the given partial range and stored in the storing unit when the second disk is reproduced by the disk reproducing unit; wherein, when the controlling unit causes the display unit to display a map based on the portion of the map data, the controlling unit causes the route guiding unit to indicate a route to a temporary destination that is as close as possible to the peripheral boundary of the given partial range of the map data along the guiding route to the destination and is a stoppable place where the vehicle is able to stop.