Method for providing additional data for a route calculation by a navigation device which comprises map data representing roads and nodal points of a road network wherein the nodal points are disposed on roads of a predetermined type, with the following steps: determining the position of the navigation device as initial position, defining an initial area in which the initial position is disposed, determining all exit points (301 to 304) on each of which one of the roads exits the initial area, selecting one of the nodal points for each of the exit points (301 to 304) as start transition nodal point (401 to 404) so that the start transition nodal point (401 to 404) is disposed at the end of a track which connects the exit point (301 to 304) with one of the nodal points outside the initial area at minimum road costs, wherein the road costs of a track which connects the start transition nodal point (401 to 404) with one of the exit points (301 to 304) at minimum road costs are assigned to the start transition nodal point (401 to 404) as cost value, selecting those of the nodal points as intermediate nodal points that are disposed outside the initial area, were not selected as start transition nodal point (401 to 404), and meet a selection criterion, wherein to each of the intermediate nodal points a cost value is assigned which is formed as sum of the minimum road costs at which the intermediate nodal point is reachable from one of the start transition nodal points (401 to 404) via roads of the predetermined type exclusively and the cost value of the start transition nodal point (401 to 404), and storing the start transition nodal points (401 to 404) with the cost values assigned to them and the intermediate nodal points with the cost values assigned to them as additional data. determining the position of the navigation device as initial position, defining an initial area in which the initial position is disposed, determining all exit points (301 to 304) on each of which one of the roads exits the initial area, selecting one of the nodal points for each of the exit points (301 to 304) as start transition nodal point (401 to 404) so that the start transition nodal point (401 to 404) is disposed at the end of a track which connects the exit point (301 to 304) with one of the nodal points outside the initial area at minimum road costs, wherein the road costs of a track which connects the start transition nodal point (401 to 404) with one of the exit points (301 to 304) at minimum road costs are assigned to the start transition nodal point (401 to 404) as cost value, selecting those of the nodal points as intermediate nodal points that are disposed outside the initial area, were not selected as start transition nodal point (401 to 404), and meet a selection criterion, wherein to each of the intermediate nodal points a cost value is assigned which is formed as sum of the minimum road costs at which the intermediate nodal point is reachable from one of the start transition nodal points (401 to 404) via roads of the predetermined type exclusively and the cost value of the start transition nodal point (401 to 404), and storing the start transition nodal points (401 to 404) with the cost values assigned to them and the intermediate nodal points with the cost values assigned to them as additional data.