, ▁approximately ▁ ▁in ▁length , ▁was ▁p aved ▁near ▁Nash ville ▁in ▁ 1 9 5 7 . ▁M - 3 2 ▁was ▁extended ▁along ▁the ▁northern most ▁section ▁of ▁M - 6 6 ▁in ▁ 1 9 6 3 . ▁ ▁M - 6 6 ▁was ▁extended ▁sou ther ly ▁from ▁Ass y ria ▁through ▁Battle ▁Creek ▁to ▁the ▁Indiana ▁state ▁line ▁replacing ▁sections ▁of ▁M - 7 8 ▁in ▁ 1 9 6 5 . ▁M - 6 6 ▁turned ▁south ▁and ▁west ▁along ▁M - 6 0 ▁and ▁new ▁highway ▁to ▁Col on . ▁The ▁segment ▁of ▁former ▁M - 7 8 ▁not ▁used ▁by ▁M - 6 6 ▁was ▁transferred ▁to ▁local ▁control . ▁The ▁final ▁section ▁of ▁M - 7 8 ' s ▁road way ▁given ▁to ▁M - 6 6 ▁extended ▁it ▁all ▁the ▁way ▁to ▁the ▁state ▁line , ▁resulting ▁in ▁a ▁north – s outh ▁trans - pen ins ular ▁highway ▁from ▁Lake ▁Michigan ▁near ▁Char le vo ix ▁to ▁Indiana . ▁M - 6 6 ▁is ▁the ▁only ▁such ▁highway ▁to ▁run ▁the ▁length ▁of ▁the ▁Lower ▁Pen ins ula . ▁The ▁extension ▁allowed ▁the ▁Green ▁Ar row ▁Association ▁to ▁promote ▁the ▁whole ▁length ▁of ▁the ▁Green ▁Ar row ▁Route ▁with ▁a ▁single ▁highway ▁number . ▁The ▁next ▁year , ▁M - 6 6 ▁was ▁r er out ed ▁through ▁Battle ▁Creek ▁to ▁use ▁the ▁completed ▁I - 1 9 4 ▁fre ew ay . ▁ ▁A ▁ 9 0 ° ▁turn ▁in