Method and apparatus for storing cartographic route data

An electronic navigation method for planning a route over at least one of a plurality of thoroughfares, from a starting location to a selected destination, said method comprising:

• associating a plurality of features with each said thoroughfare;
• associating said selected features to form lengths of features;
• associating selected said lengths of features to form networks of said lengths;
• determining whether said selected destination and said starting location are within the same said feature, and when said selected destination and said starting location are within the same said feature, defining said route on said common feature;
• when said selected destination and said starting location are not within the same said feature, determining whether said selected destination and said starting location are within the same said link and,
• when said selected destination and said starting location are within the same said link, defining said route on said common link;
• and
• when said selected destination and said starting location are not within the same said link, determining whether said selected destination and said starting location are on the same network and, when said selected destination and said starting location are on the same network, defining said route on said common network.

A navigation device comprising:

• a processor;
• a display, connected to said processor;
• a memory connected to said processor, said memory containing cartographic data, including a thoroughfare having a name, wherein at least a portion of said thoroughfare is displayed on said display;
• and
• an input, said input being operable to identify any point on said portion of said thoroughfare displayed on said display, whereupon such identification said processor retrieves said name of said thoroughfare from said memory and displays said name on said display.

A cartographic data storage device comprising:

• a plurality of first level records, wherein each record in said first level contains at least one of a name of a thoroughfare, a thoroughfare classification of a thoroughfare, and data indicative of a change in cartographic coordinates of a section of said thoroughfares;
• a plurality of second level records, wherein each of said records in said second level contains selected records of said first level;
• and
• a plurality of third level records, wherein each said record on said third level contain records of said second level having a matching said name,
• wherein a sorted list containing a field sorted by said name, a field sorted by an X-coordinate of said cartographic coordinates, a field sorted by a Y-coordinate of said cartographic coordinates, and a field sorted by said thoroughfare classification is utilized to construct said second level records and said third level records.