Navigation system for use in vehicle

Claim 1

A navigation system comprising: (a) a display unit; (b) map information storage means for storing map information, said map information including intersections, a net of roads, and administrative districts; (c) destination input mode executing means for executing a destination input mode to determine a destination intersection; (d) optimum route computation means for computing an optimum route from a starting point intersection to said destination intersection; (e) current position detection means for detecting a current position of a vehicle; and (f) route guidance display means for displaying route guiding information on said display unit based on the optimum route and the current position; wherein said destination input mode executing means includes: (i) first list means for listing names of the administrative districts on said display unit; (ii) administrative district input means for inputting one of the listed administrative districts; (iii) second list means for listing names of transit roads passing through the inputted administrative district on said display unit; (iv) first road input means for inputting one of the listed transit roads as a first road; (v) third list means for listing names of intersecting roads on said display unit, the intersecting roads intersecting said first road and passing through the inputted administrative district; (vi) second road input means for inputting one of the listed intersecting roads as a second road; and (vii) intersection determination means for determining said destination intersection formed by said inputted first and second roads.