A milestone is a numbered marker placed on a route such as a road, railway line, canal or boundary. They can indicate the distance to towns, cities, and other places or landmarks like mileage signs; or they can give their position on the route relative to some datum location (a zero milepost). On roads they are typically located at the side or in a median or central reservation. They are alternatively known as mile markers (sometimes abbreviated MMs), mileposts or mile posts (sometimes abbreviated MPs). A "kilometric point" is a term used in metricated areas, where distances are commonly measured in kilometres instead of miles. "Distance marker" is a generic unit-agnostic term.
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Milepost in the context of Saxon post milestone
A Saxon milepost (German: kursächsische Postmeilensäule, colloquially sächsische Postmeilensäule or Postsäule) was a milepost in the former Electorate of Saxony that gave distances expressed as journey times to the nearest eighth of an hour. With one hour being the equivalent of one league, this corresponds to a distance of about 566 m. The design of the mileposts varied according to the distance at which they were placed. They were hewn from natural stone into the shape of an obelisk, an ancient herma or a stele. Their prototype was the Roman milepost. From its German name römische Meilensäule the rather inaccurate German description of Säule (lit.: "column") was derived. The Saxon head postal director (Oberpostdirektor), Paul Vermehren, brought about their inception based on official distance surveys, whose results were given in leagues on the post mileposts. A league in Saxony at that time (1722 to 1840) was meant to be an hour's journey, equivalent to half a mile or 4.531 kilometres.
Saxon postal mileposts were set up during the reign of August the Strong and his successor along all important postal and trading routes and in almost all towns in the Electorate of Saxony to indicate the official distances. This was intended to be the basis for the creation of a unified calculation of postal charges. Because the territory of the Electorate of Saxony was larger than that of the present-day German state of Saxony, these mileposts are nowadays also found in the states of Thuringia, Brandenburg and Saxony-Anhalt, as well as in Poland.
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