Digital cartography is hard. Even without various intentional errors and distortions (many maps contain intentional dimensional non-linearities for "strategic r

Digital cartography is hard. Even without various intentional errors and distortions (many maps contain intentional dimensional non-linearities for "strategic reasons", ie. so that they cannot be directly used for directing artilery fire) the input data is full of various unintentional noise and non-sense because of the processes that were used in acquiring and digitizing that data in the first place. Processes ranging from digitizing paper maps of generally unknown accuracy with digitizer to just guessing positions of things from sharpie marks on hand-drawn map created by who knows who in the field. Trying to make some sense of such data was my first real IT job.