Patent ID: 8179287

Claim:
A navigation system having a server apparatus with a route search module for searching a route to a destination and a client apparatus including a communication module for communicating with said server, wherein; said server apparatus comprising: a map generation module for generating a route periphery map which is a map of a route peripheral vicinity including said route; a map modification module for modifying said route periphery map generated at said map generation module; and a map data base being referenced while generating said route periphery map; said client apparatus comprising: a vehicle position detection apparatus for detecting a position of the vehicle; and a display module for displaying said route periphery map, wherein said map generation module generates said route periphery map by dividing said route periphery map into a plurality of vicinities having different degrees of fineness, said map modification module modifies a shape of at least one map element that intersects a boundary between a first vicinity and a second vicinity having different degrees of fineness, at connecting points provided on said boundary, so that said shape of said map element is continued between said first and second vicinities, if said map element comprises road data, said map modification module divides said road data intersecting with said boundary at a common node in said first and second vicinities located closest to said boundary, and if said map element comprises background data, said map modification module retains all of a first portion of said background data for which a degree of fineness of the map element is simpler than a second portion of said background data.