M-99 is a north–south state trunkline highway in the Lower Peninsula of the US state of Michigan. It runs from the Ohio state border, where it connects to State Route 15 (SR 15), north to Lansing, where it terminates at a junction with Interstate 496 (I-496). The highway mainly serves local communities along the route as it passes through farm lands in the southern part of the state. One short segment, in Jonesville, is routed concurrently with US Highway 12 (US 12). The segment within Lansing follows Martin Luther King Jr. Boulevard.
M-28 is an east–west state trunkline highway that traverses nearly all of the Upper Peninsula of the U.S. state of Michigan, from Wakefield to near Sault Ste. Marie in Bruce Township. Along with US Highway 2 (US 2), M-28 forms a pair of primary highways linking the Upper Peninsula from end to end, providing a major access route for traffic from Michigan and Canada along the southern shore of Lake Superior. M-28 is the longest state trunkline in Michigan numbered with the "M-" prefix at 290.373 miles (467.310 km). The entire highway is listed on the National Highway System, while three sections of M-28 are part of the Lake Superior Circle Tour. M-28 also carries two memorial highway designations along its route.
M-79 is an east–west state trunkline highway in the central portion of Lower Peninsula of the U.S. state of Michigan. The western terminus is about three miles (4.8 km) southeast of Hastings at the junction with M-37 and the eastern terminus is in downtown Charlotte at the junction with M-50 and Business Loop Interstate 69 (BL I-69). It passes through Quimby and Nashville, where there is a junction with M-66. The entire highway is undivided surface road. It has no direct access with Interstate 69 (I-69), although a sign for the highway is located on southbound I-69 at exit 61.
M-46 is an east–west state trunkline highway in the US state of Michigan between Muskegon and Port Sanilac, terminating near Lake Michigan and Lake Huron on each end. Except for the north–south segment that corresponds with the US Highway 131 (US 131) freeway between Cedar Springs and Howard City, M-46 is practically a due east–west surface highway. The road runs through rural sections of the Lower Peninsula connecting several freeways including US 31, US 131, US 127 and Interstate 75 (I-75).
H-63 is a county-designated highway (CDH) in the Upper Peninsula of the US state of Michigan. The highway parallels the Interstate 75 (I-75) corridor between St. Ignace and Sault Ste. Marie. The road is called Mackinac Trail after the Upper Peninsula branch of an Indian trail used before European settlers reached the area. Originally, the roadway was built as a section of US Highway 2 (US 2) before being added to the CDH system in the 1970s.
M-76 is a former state trunkline highway designation in the Lower Peninsula of the US state of Michigan. The highway's designation was decommissioned when the last section of it was converted to freeway as a part of the present-day Interstate 75 (I-75). At that time, M-76 extended from US Highway 23 (US 23) near Standish northwesterly to I-75 south of Grayling. Two sections of the route followed freeways with a two-lane highway in between to connect them. The former routing of M-76 through West Branch before that city was bypassed was initially redesignated Business M-76. The highway itself ran through mixed fields and forests bypassing several other towns in the region.
M-120 is a state trunkline highway in the US state of Michigan in the southwest Lower Peninsula. The highway runs northeast from Muskegon to Hesperia. In between, the road passes through suburban Muskegon, forests and farmland. Some 5,900–26,000 vehicles use the highway each day on average as it runs long a series of roads that follow county lines in the area.
M-91 is a largely north–south state trunkline highway in the Lower Peninsula of the US state of Michigan. It runs from Belding to south of Lakeview. Its 24-mile (39 km) length exists entirely within Ionia and Montcalm counties. It is all undivided surface route. Aside from the two Michigan state highways that are its termini, it has only one other intersection with any Michigan state highway, and that is with M-57 in Greenville.
M-57 is an east–west state trunkline highway in the US state of Michigan. The 105.377-mile (169.588 km) highway connects US Highway 131 (US 131) near Rockford on the west end to M-15 near Otisville in the Lower Peninsula. In between, the mostly rural highway passes through farmland and connects several highways and smaller towns together. Three of these highways are freeways: US 131, US 127 and Interstate 75 (I-75). Along the way, between 3,700 and 22,300 vehicles use the highway daily.
US Highway 27 (US 27) is a part of the US Highway System that now runs from Miami, Florida, to Fort Wayne, Indiana. In the US state of Michigan, it was a north–south state trunkline highway that entered the state south of Kinderhook and ended south of Grayling. Its route consisted of a freeway concurrency with Interstate 69 (I-69) from the state line north to the Lansing area before it followed its own freeway facility northward to St. Johns. From there north to Ithaca, US 27 was an expressway before continuing as a freeway to a terminus south of Grayling.
M-134 is an east–west state trunkline highway in the Upper Peninsula (UP) of the US state of Michigan. It connects Interstate 75 (I-75) north of St. Ignace with the communities of Hessel, Cedarville and De Tour Village along Lake Huron. East of De Tour, the highway crosses the De Tour Passage on a ferry to run south of the community of Drummond on Drummond Island. It is one of only three state trunklines in Michigan on islands; the others are M-154 on Harsens Island and M-185 on Mackinac Island. M-134 is also one of only two highways to utilize a ferry in Michigan; the other is US Highway 10 (US 10) which crosses Lake Michigan from Manitowoc, Wisconsin, to Ludington. Most of the mainland portion of M-134 is also part of the Lake Huron Circle Tour, and since 2015, it has been a Pure Michigan Byway under the name M-134 North Huron Byway.
M-48 is an east–west state trunkline highway in the Upper Peninsula (UP) of the US state of Michigan. It connects Rudyard with Pickford and continues to the far eastern end of the UP. The highway runs for 43.723 miles (70.365 km) through rural parts of Chippewa County, including along the county line with Mackinac County. Between 580 and 1,800 vehicles a day use the roadway daily.
M-82 is a state trunkline in the Lower Peninsula in the US state of Michigan that travels between Fremont and Howard City. The section between Newaygo and Howard City travels through Fremont and along the southern edge of Manistee National Forest. The current version of M-82 is actually the second in the state; the first usage appeared in the Upper Peninsula by 1919. The Lower Peninsula routing has been in use since the 1920s. Various extensions and truncations have shifted the terminus as far west as New Era or Hesperia in the past. The current route was finalized in the late 1970s
There have been nine business routes for Interstate 75 in the US state of Michigan. Numbered either Business Loop Interstate 75 or Business Spur Interstate 75 depending if they are a full business loop or a business spur, these highways are former routings of I-75's predecessor highways in the state. They were designated as I-75 was completed through the various areas of Michigan. The business loop in Pontiac runs through that city's downtown along a section of Woodward Avenue and a segment of roadway formerly used by M-24. The former Saginaw business loop was once a part of US Highway 23 (US 23), as was most of the original Bay City business loop. The roadways that make up the business loops in West Branch and Roscommon were previously part of M-76, I-75's predecessor through that part of the state. In Northern Michigan, the Grayling and Gaylord BL I-75s were part of US 27, and the two business routes in St. Ignace and Sault Ste. Marie in the Upper Peninsula of Michigan were part of US 2. A tenth business route, a loop through Indian River has been proposed. Each of the business loops connects to I-75 on both ends and runs through their respective cities' downtown areas. The two business spurs only connect to I-75 on one end and run into the appropriate downtown.
Business M-28 was a state trunkline highway in the Upper Peninsula of Michigan. It served as a business route running for 9.010 miles (14.500 km) through the Newberry area. The business loop followed a U-shaped routing to connect downtown Newberry with M-28 south of town. It ran west of the city of Newberry, passing through the community of Dollarville before entering downtown, turning south and ending near the county airport.
US Highway 2 (US 2) is a component of the United States Numbered Highway System that connects Everett, Washington, to the Upper Peninsula (UP) of the US state of Michigan, with a separate segment that runs from Rouses Point, New York, to Houlton, Maine. In Michigan, the highway runs through the UP in two segments as a part of the state trunkline highway system, entering the state at Ironwood and ending at St. Ignace; in between, US 2 briefly traverses the state of Wisconsin. As one of the major transportation arteries in the UP, US 2 is a major conduit for traffic through the state and neighboring northern Midwest states. Two sections of the roadway are included as part of the Great Lakes Circle Tours, and other segments are listed as state-designated Pure Michigan Byways. There are several memorial highway designations and historic bridges along US 2 that date to the 1910s and 1920s. The highway runs through rural sections of the UP, passing through two national and two state forests in the process.
The Whitefish Bay National Forest Scenic Byway is a National Forest Scenic Byway that runs along Whitefish Bay in the Hiawatha National Forest in the U.S. state of Michigan. The byway mostly follows Federal Forest Highway 42 (FFH 42) through Chippewa County in the Upper Peninsula. As a forest highway, it is maintained jointly by the Chippewa County Road Commission (CCRC) and the U.S. Forest Service (USFS). The route of the byway first existed as an earth road by the 1930s; it was improved into a gravel road in the 1940s and paved between the 1950s and the 1980s. The byway designation was created in 1989.
Lake Huron Circle Tour 
M-134 in Cedarville 
M-48 in Pickford 
M-28 near Dafter 
BL I-75 in Sault Ste. Marie 
