Wisconsin/Highway Classification

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This is a draft. Feel free to contrubute where you can.

This page describes Wisconsin-specific determinations for implementing US highway classification values.



Motorways (freeways) are fully grade separated without at-grade intersections, railroad crossings, etc. To know if the Wisconsin DOT considers a particular road is a freeway, see the WIDOT highway map or look for "Freeway ends" signs.


The trunk/motorway network should connect all tier 1 cities in the state. To determine the trunk routing, a helpful tool is to consider the Wisconsin DOT publishes Connections Transportation Plan which outlines the state's priority corridors. The trunk routing should use these corridors whenever possible.


  • All US highways are primary (except when they are a freeway or are deemed to be highway=trunk
  • Wisconsin State Highways are also important enough to be highway=primary. This is often evidenced by their inclusion in the National Highway System.
  • Major Urban Arterial roads connecting cities and their major suburbs (above 7500 population).


  • Wisconsin State Highway Routes should be highway=secondary unless deemed to be primary.
  • Some county highways should also be highway=secondary given they form an important connection between towns of population greater than 2500,
  • Minor arterial roads connecting parts of the city


  • The majority of county highways should be highway=tertiary.
  • Urban collector roads


Expressways are partially grade separated including some grade separations, but may include some at grade crossings. To know if the Wisconsin DOT considers a particular road is a expressway, see the WIDOT highway map or look for "Expressway ends" signs.

City Importance

Tier 1

Tier 1 cities should be connected with a highway=motorway or highway=trunk (in paratheses are other significant cities in the same area)

  • Milwaukee (Waukesha, West Allis, Wauwatosa, Brookfield, New Berlin, Greenfield, Oak Creek, Mequon, Muskego)
  • Madison (Sun Prairie, Fitchburg)
  • Green Bay (De Pere)
  • Kenosha
  • Racine
  • Appleton (Neenah)
  • Eau Claire
  • Oshkosh
  • Janesville-Beloit
  • La Crosse
  • Sheboygan
  • Fond du Lac
  • Wausau
  • Marinette
  • Watertown (alongside Jefferson and Fort Atkinson, which form a linear corridor of cities).

In addition the following MSAs connect to Wisconsin:

  • Chicago, IL
  • Minneapolis/Saint Paul, MN
  • Deluth, MN (Superior, WI)
  • Dubuque, IA
  • Rockford, IL

Tier 2

Tier 2 cities should be connected with a highway=primary or greater.

Tier 2 cities are:

  • Municipalities with at least 7500 population
  • Most important city in a county regardless of population (Usually county seats in remote areas of the state e.g. Crandon)

Tier 3

Since Wisconsin state highways aim to connect every town with population at least 2 500, this is a natural place to designate cities as tier 3. In general, since state highways are at least highway=secondary, this is already accomplished.