A navigation system guides a user to a destination with an improved arrival detection capability when the selected destination is a large facility or a natural place that occupies a relatively large area. When a particular destination is specified by the user, the navigation system calculates a route to the destination based on the address of the specified destination. The navigation system also checks whether the specified destination is associated with polygon data. When the specified destination is associated with the polygon data, the navigation system creates an arrival detection start range. After reaching the arrival detection start range, the navigation system detects the arrival at the destination when any part of the polygon of the destination comes within an arrival detection range of the navigation system.