Michigan Highways
The State Trunkline Highway System of the US state of Michigan is a network of roads owned and maintained by the Michigan Department of Transportation (MDOT). The most prominent of these roads are part of one of three numbered highway systems in Michigan: Interstates Highways, US Highways, and the other State Trunklines. Other systems of roads are operated by the 83 counties in the state as well as each city.
Interstate Highways and US Highways are assigned at the national level. Interstate Highways are numbered in a grid—even-numbered highways are east–west highways (with the lowest numbers along Mexico and the Gulf of Mexico), and odd-numbered highways are north–south highways (with the lowest numbers along the Pacific Ocean). US Highways are also numbered in a grid—even numbered for east–west highways (with the lowest numbers along Canada) and odd numbered for north–south highways (with the lowest numbers along the Atlantic Ocean). For this reason, mainline (two-digit) Interstate Highways in Michigan all have numbers above 69 and mainline US Highways all have numbers below 45. Three-digit Interstate and U.S. Highways, also known as "child routes," are branches off their main one- or two-digit "parents". The Interstate and US Highways are maintained by MDOT. Interstate 75 (I-75) and US Highway 23 (US 23) are the longest examples in the state.
State Trunklines are the other state highways maintained by MDOT. These highways are completely owned and maintained by the state. Michigan highways are properly referred to using the M and never as "Route 28" or "Highway 115", but as M-28 or M-115. The marker used for state trunklines is a diamond with a block-letter "M" at the top. Roads that are maintained by the state but not assigned a state trunkline designation carry an unsigned highway designation.
County-Designated Highways are assigned numbers in a zone system by MDOT, but maintained by the counties. Each zone is indicated by a letter A–H which is followed by a number based on a grid inside that zone. Each county also maintains any other roadway that is not a state trunkline or a city street. The numbering and signing practices vary from county to county, as does the size of each county's system. Numerical designations typically do not carry over from one county to the next; a CDH that crosses county lines keeps its designation in each county however. County road designations are typically abbreviated "CR" or "Co Rd" followed by the number, and CDHs are abbreviated to just their letter and number assignment.
Recognized content - 
Interstate 75 (I-75) is a part of the Interstate Highway System that runs north–south from Miami, Florida, to Sault Ste. Marie in the Upper Peninsula of the US state of Michigan. I-75 enters the state from Ohio in the south, north of Toledo, and runs generally northward through Detroit, Flint, and Bay City, crosses the Mackinac Bridge, and ends at the Canadian border in Sault Ste. Marie. The freeway runs for approximately 396 miles (637 km) on both of Michigan's major peninsulas. The landscapes traversed by I-75 include Southern Michigan farmland, northern forests, suburban bedroom communities, and the urban core of Detroit. The freeway also uses three of the state's monumental bridges to cross major bodies of water. There are four auxiliary Interstates in the state related to I-75, as well as nine current or former business routes, with either Business Loop I-75 (BL I-75) or Business Spur I-75 (BS I-75) designations.
The freeway bears several names in addition to the I-75 designation. The southern segment was called the Detroit–Toledo Expressway during planning in the 1950s and 1960s. Through Detroit, I-75 is the Fisher Freeway or the Walter P. Chrysler Freeway, named for pioneers in the auto industry. Sections on either side of the Mackinac Bridge are the G. Mennen Williams Freeway or the Prentiss M. Brown Freeway, named for politicians who helped get the bridge built. Officially, the entire length is the American Legion Memorial Highway, after the organization of the same name. Various sections carry components of the four Great Lakes Circle Tours in the state. (Full article...)
General images
-
M-553 approaching Glass' Curve south of Marquette -
H-58 west of Grand Marais -
Planning map for the Detroit area freeways from 1955 -
Interstate HighwaysOther freewaysMiscellaneous expressways -
Junction between M-28 and M-178 south of Munising before 1941 -
M-121 in Jenison -
Grand River Avenue, once a part of M-16 and later US 16, was originally an Indian trail converted as a plank road before becoming a state highway. -
M-87 on November 1, 1956 -
Exit 254 on I-75 south of Grayling -
Dead Man's Curve along the Marquette–Negaunee Road shown in 1917 with its hand-painted centerline, the first in the nation -
Welcome sign along US 8 -
M-39 bridge over the River Rouge in Dearborn -
Map of the zone system -
H-13 during winter -
Map of the pre-statehood Indian trails -
A-2 in Allegan County south of Holland -
Construction along I-96 for the interchange with M-231 in July 2013 (from Michigan State Trunkline Highway System) -
Milemarker used in 1922 for M-14
.jpg)
.JPG)
Selected picture
Topics
State Trunkline System, overview of the system
- Interstates Highways in the state
- US Highways in the state
- State Trunklines
- County-Designated Highways in the state
- Pure Michigan Byways, a system of scenic, historical or recreational highways in the state
- Great Lakes Circle Tour
Subcategories
Related portals
WikiProjects
Things to do
Nominations and votes for selected articles and selected pictures are always needed. Anyone can nominate an article, and anyone can vote for an article. You can also recommend items for Did you know?. Improvements to the articles are always welcome as the project works on expanding and nominating the remaining ones for Good Article or Featured Article status.
