Open main menu

Wikipedia β

Portal:Michigan highways

  (Redirected from Portal:Michigan Highways)
PortalsTechnologyTransportRoadsU.S. RoadsMichigan Highways

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 (but the lowest numbers are 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.

Selected article

Cross Street, one way in Ypsilanti

M-17 is a 6.390-mile-long (10.284 km) state trunkline highway connecting the cities of Ypsilanti and Ann Arbor in Washtenaw County. It was once part of a highway that spanned the southern Lower Peninsula before the creation of the U.S. Highway System in 1926. The designation once extended into downtown Detroit, but the eastern terminus was progressively scaled back in the late 1960s to the current location in Ypsilanti. The changes made to the highways in Washtenaw County spawned Business M-17, a business loop for 11 years between 1945 and 1956. (more...)

Recently selected: M-183 • I-94 • H-63

Did you know...

The Tridge in winter

Categories

Selected picture

M-28 & M-178.jpg
Junction of M-28 and M-178 south of Munising before 1941

Recently selected: M-1 • US 41/M-28 • Bus. US 12/M-17

Topics

State Trunkline System, overview of the system

Related portals

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.