1It is curious that the O.S. have a 10 m contour interval at present both for the 1:50 000 and 1:25 000 scale maps in the Lake District. Worse, they make the contour lines thicker on the 1:50 000, so darking the map further in hilly areas like the Lakes. Some other Explorer maps use 5 m contour interval, but not the maps of the Lake District – a good thing.