 The 1927 edition of the official Michigan highway service map was the first to show M @-@ 28 extended along US 41 into Marquette County and east over the former M @-@ 25 through Munising and Newberry , before ending in downtown Sault Ste . Marie . At Negaunee , M @-@ 28 was shown along the previous routing of M @-@ 15 between Negaunee and Marquette for 10 miles ( 16 km ) , while US 41 ran along a portion of M @-@ 35 . This southern loop routing of M @-@ 28 lasted until approximately 1936 , when M @-@ 28 was displayed as concurrent with US 41 . The former route is now Marquette County Road 492 ( CR 492 ) . Around 1930 , the northern terminus of US 41 was extended east from Copper Harbor to Fort Wilkins State Park . Another realignment shown in 1937 marked the transfer of US 41 / M @-@ 28 out of downtown Ishpeming and Negaunee . This former routing later became Bus . M @-@ 28 . The highway was realigned due north between Rapid River and Trenary according to the 1938 service map . US 41 was completely paved in 1951 . The final two sections to be paved were in Baraga County and Keweenaw County . 
