Missouri supplemental route

Highway system

A supplemental route is a state secondary road in the U.S. state of Missouri, designated with letters. Supplemental routes were various roads within the state which the Missouri Department of Transportation was given in 1952 to maintain in addition to the regular routes, though lettered routes had been in use from at least 1932. The four types of roads designated as Routes are:Farm to market roads Roads to state parks Former alignments of U.S. or state highways Short routes connecting state highways from other states to routes in Missouri

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