A method of correcting digitized map data of a cross-like junction to a roundabout, wherein the digitized map data is provided by a map data supplier and stored in a map database of a navigation device, the map data comprising routing data in the form of route links and shape points, wherein each route link is associated with a sequence of shape points representing a course of a road segment (20, 21) for display on a screen (100, 1030), the method comprising the steps of: - detecting a first user input operation indicative of a selection of a road segment (20, 21) at a junction node (d) of a cross-like junction displayed on the screen (100, 1030), the road segment (20, 21) corresponding to a route link of the map database provided by the map data supplier; - displaying, based on the map data provided by the map data supplier, at least one existing shape point (a - j) of the sequence of shape points (3, 4, 6, 8) stored in the map database for the selected road segment (20, 21); - detecting at least one second user input operation indicative of a graphical manipulation of the course of the selected road segment (20, 21) on the screen (100, 1030), wherein the graphical manipulation comprises a positional displacement of a specific existing shape point (i) adjacent to the junction node (d) displayed on the screen by shifting the specific existing shape point (i) from the displayed screen position to a new screen position; - generating on basis of the detected second user input operation corrected routing data reflecting the manipulated course of the selected road segment (20, 21); - converting the junction node (d) to an unreferenced data element, to which no shape line references, in the routing data; - changing existing shape lines (3, 4, 6, 8), which all reference from an adjacent shape point (c, e, g, i) to the junction node (d) to reference from the respective adjacent shape point (c, e, g, i) to a respective neighboring shape point (c, e, g, i) of the adjacent shape points (c, e, g, i); and - storing the corrected routing data in the map database by overwriting the existing routing data of the selected road segment (30, 40, 60) without modifying a structure of the original map database provided by the map data supplier. - detecting a first user input operation indicative of a selection of a road segment (20, 21) at a junction node (d) of a cross-like junction displayed on the screen (100, 1030), the road segment (20, 21) corresponding to a route link of the map database provided by the map data supplier; - displaying, based on the map data provided by the map data supplier, at least one existing shape point (a - j) of the sequence of shape points (3, 4, 6, 8) stored in the map database for the selected road segment (20, 21); - detecting at least one second user input operation indicative of a graphical manipulation of the course of the selected road segment (20, 21) on the screen (100, 1030), wherein the graphical manipulation comprises a positional displacement of a specific existing shape point (i) adjacent to the junction node (d) displayed on the screen by shifting the specific existing shape point (i) from the displayed screen position to a new screen position; - generating on basis of the detected second user input operation corrected routing data reflecting the manipulated course of the selected road segment (20, 21); - converting the junction node (d) to an unreferenced data element, to which no shape line references, in the routing data; - changing existing shape lines (3, 4, 6, 8), which all reference from an adjacent shape point (c, e, g, i) to the junction node (d) to reference from the respective adjacent shape point (c, e, g, i) to a respective neighboring shape point (c, e, g, i) of the adjacent shape points (c, e, g, i); and - storing the corrected routing data in the map database by overwriting the existing routing data of the selected road segment (30, 40, 60) without modifying a structure of the original map database provided by the map data supplier.