A navigation system may determine an approximate position of a navigation device and determine a geographical area in which the navigation device is located based on the approximate position. The determined geographical area may be one of a plurality of geographical areas included in a routing area. Each geographical area may be associated with one of a plurality of positioning procedures each associated with a predetermined parameter set. The navigation system may select the positioning procedure associated with the determined geographical area and determine the position of the navigation device according to the selected positioning procedure and the associated predefined parameter set.