1. A method of performing a road network search for vehicle navigation, the method comprising: determining a current location of the vehicle using a navigation system; the navigation system retrieving digital map data in a vicinity of the current location, the digital map data including a set of road segments, each being associated with a hierarchy class and an elevation; the navigation system calculating a road segment-specific weighting factor for road segments included in the set of road segments, the calculation by the navigation system of the weighting factor using a distance between a specific road segment and the current location, and an elevation of the specific road segment; the navigation system selectively discarding the road segments from the set of road segments, based on the weighting factor and the associated hierarchy class, to obtain an updated set of road segments; and the navigation system performing the road network search by expanding route links based on the updated set of road segments.