Red lines show how the total change of direction increases in turns. For example, as a line reaches value 90, the road will have made a 90° right turn. At each inflection point, the line starts at zero again. The blue lines give an idea of the curvature, expressed as degrees change of direction per 10m (higher values correspond with steeper red lines). On the x-axis: position on the route in kilometres. Analysis dirkmjk.