Charles Perrault had not invented the famed boots, which really did exist in his days and were a part of the uniform of a postman. The name itself comes from the distance of seven leagues, about three miles, which was a standard distance between the posts introduced by the administration of Louis XIV where Perrault was an important official.
It took up to twelve days to send a letter from Versailles to any major French city, and fifteen to travel by post with a price of the first class fixed at 125 livres (a year of artisanal wages) and the third class at 50 livres. Travelling alone was a dangerous business, and quite often the postmen were robbed and killed. The boots you see above are on display at the Musee de la Poste, near Montparnasse, not built for walking, but rather to kick anyone who gets anywhere near your horse.