1. A vehicle navigation system comprising: a map database having navigable features of a geographic area stored therein; a central processing unit electrically coupled to the locator device; an origin input device electrically coupled to the central processing unit operable to acquire a course origin; a destination input device electrically coupled to the central processing unit operable to acquire a course destination; a course planning computer program operable to instruct the central processing unit to plan a course between the course origin and the course destination, the course consisting of primary navigable features selected from the navigable features stored in the map database; and a course modification computer program operable to instruct the central processing unit to acquire alternate course data, and to replace the primary navigable features of the course with the alternate course data.