How each state handles extremely minor highways

[NE2]

Different states handle very minor (but still primary) highways in different ways. I'm talking about roads like frontage roads, tiny old alignments, or block-long connectors that are still state maintained.

Some states don't care, because numbering and maintenance are not linked in any meaningful way:
*Alaska
*Illinois?
*Maine?
*Massachusetts
*New Hampshire
*Rhode Island

Some states simply assign numbers in the normal scheme:
*Alabama?
*Florida (recently assigned new numbers to frontage roads and such)
*Hawaii
*Kentucky
*Louisiana (often with number suffixes)
*Maryland (often with letter suffixes)
*Mississippi
*New Jersey

Some simply append a letter suffix or banner to a route they spur from:
*Arizona
*Arkansas
*California
*Colorado
*Georgia (connector, loop, and spur)
*Michigan (connector and old)
*Minnesota (UNU/UNM, formerly numbered 8xx/9xx)
*Missouri
*Ohio
*South Carolina (connector)
*Virginia (Y)
*West Virginia (spur)

Some states have a second numbering system that every state highway gets a number from, usually completely different from the signed numbers:
*Delaware
*Montana
*New York (state highway numbers, but also see below)
*Oregon

Some states have separate numbering systems or classes for minor routes, or only call them by name:
*Connecticut (4xx+)
*Iowa (9xx)
*Nebraska (link and spur)
*Nevada (frontage)
*New Mexico (frontage)
*New York (9xx)
*Oklahoma (all numbered 0?)
*Pennsylvania (four-digit routes)
*Texas (loop and spur)
*Vermont (9xx plus 'X State Highway' names)
*Virginia (frontage)

Unknown:
*Idaho
*Indiana
*North Carolina
*North Dakota
*South Dakota
*Tennessee
*Utah
*Wisconsin
*Wyoming

[ElishaGOtis]

Different states handle very minor (but still primary) highways in different ways. I'm talking about roads like frontage roads, tiny old alignments, or block-long connectors that are still state maintained.

Some states don't care, because numbering and maintenance are not linked in any meaningful way:
*Alaska
*Illinois?
*Maine?
*Massachusetts
*New Hampshire
*Rhode Island

Some states simply assign numbers in the normal scheme:
*Alabama?
*Florida (recently assigned new numbers to frontage roads and such)
*Hawaii
*Kentucky
*Louisiana (often with number suffixes)
*Maryland (often with letter suffixes)
*Mississippi
*New Jersey

Some simply append a letter suffix or banner to a route they spur from:
*Arizona
*Arkansas
*California
*Colorado
*Georgia (connector, loop, and spur)
*Michigan (connector and old)
*Minnesota (UNU/UNM, formerly numbered 8xx/9xx)
*Missouri
*Ohio
*South Carolina (spur)
*Virginia (Y)
*West Virginia (spur)

Some states have a second numbering system that every state highway gets a number from, usually completely different from the signed numbers:
*Delaware
*Montana
*Nevada (frontage)
*New Mexico (frontage)
*New York (state highway numbers, but also see below)
*Oregon
*Virginia (frontage)

Some states have separate numbering systems or classes for minor routes, or only call them by name:
*Connecticut (4xx+)
*Iowa (9xx)
*Nebraska (link and spur)
*New York (9xx)
*Oklahoma (all numbered 0?)
*Pennsylvania (four-digit routes)
*Texas (loop and spur)
*Vermont (9xx plus 'X State Highway' names)

Unknown:
*Idaho
*Indiana
*North Carolina
*North Dakota
*South Dakota
*Tennessee
*Utah
*Wisconsin
*Wyoming

From my research, NC is interesting as they have the primary routes directly signed, and the secondary routes indirectly signed. Sometimes they're posted on street blades but that's about it. Many of these secondary routes are duplicated.

[elsmere241]

From my research, NC is interesting as they have the primary routes directly signed, and the secondary routes indirectly signed. Sometimes they're posted on street blades but that's about it. Many of these secondary routes are duplicated.

Secondary roads in North Carolina have a different set of numbers in each county.

[wriddle082]

Different states handle very minor (but still primary) highways in different ways. I'm talking about roads like frontage roads, tiny old alignments, or block-long connectors that are still state maintained.

Some states don't care, because numbering and maintenance are not linked in any meaningful way:
*Alaska
*Illinois?
*Maine?
*Massachusetts
*New Hampshire
*Rhode Island

Some states simply assign numbers in the normal scheme:
*Alabama?
*Florida (recently assigned new numbers to frontage roads and such)
*Hawaii
*Kentucky
*Louisiana (often with number suffixes)
*Maryland (often with letter suffixes)
*Mississippi
*New Jersey

Some simply append a letter suffix or banner to a route they spur from:
*Arizona
*Arkansas
*California
*Colorado
*Georgia (connector, loop, and spur)
*Michigan (connector and old)
*Minnesota (UNU/UNM, formerly numbered 8xx/9xx)
*Missouri
*Ohio
*South Carolina (spur)
*Virginia (Y)
*West Virginia (spur)

Some states have a second numbering system that every state highway gets a number from, usually completely different from the signed numbers:
*Delaware
*Montana
*Nevada (frontage)
*New Mexico (frontage)
*New York (state highway numbers, but also see below)
*Oregon
*Virginia (frontage)

Some states have separate numbering systems or classes for minor routes, or only call them by name:
*Connecticut (4xx+)
*Iowa (9xx)
*Nebraska (link and spur)
*New York (9xx)
*Oklahoma (all numbered 0?)
*Pennsylvania (four-digit routes)
*Texas (loop and spur)
*Vermont (9xx plus 'X State Highway' names)

Unknown:
*Idaho
*Indiana
*North Carolina
*North Dakota
*South Dakota
*Tennessee
*Utah
*Wisconsin
*Wyoming

From my research, NC is interesting as they have the primary routes directly signed, and the secondary routes indirectly signed. Sometimes they're posted on street blades but that's about it. Many of these secondary routes are duplicated.

NC's secondary highway numbers (which are almost always four digit) are duplicated on a per county basis.  They may be maintained by the state but act more like county roads, just like Virginia or West Virginia.  A road may have one number in one county, then cross a county line and the number changes.

In Tennessee, the most minor roads are almost always locally maintained, either by the county or the municipality.  I am aware of only two counties that number their county roads: McMinn and Monroe, and they both use the standard blue pentagon.

[NWI_Irish96]

For Indiana, roads maintained by the state get route numbers and those that aren't, don't. There are very few exceptions.

Minor routes get 3di numbers that closely parallel and/or connect to a "parent" route, though there are 3di routes that aren't exactly minor.

[KeithE4Phx]

Wisconsin has been assigning letters to its county-maintained roads almost as long as it's had a state highway system (1917).  Missouri does the same, but theirs are secondary state roads, not county.

Minnesota has its own system of county highway numbers.

California, Illinois, Iowa, and (I think) Michigan assign county route numbers in a statewide grid.  The numbers vary by state, but they are all alphanumeric, beginning with A1 and ending at the opposite end of the state.  Each state is unique.

Many, but not all Arizona counties assign numbers to county routes.  The Loop, Spur, Truck, etc. highways are state-maintained, although not all are signed.  Marked county roads don't usually follow the state highway number.  For example, AZ 96 in Hillside becomes Yavapai County 62, and AZ 373 in Greer becomes Apache County 1120.  Both roads are signed.  AZ 238 becomes Maricopa County 238 at Mobile, but it isn't signed (at least not yet).

Indiana numbers most of its county roads in a grid system.  They're labeled using street blades instead of signs.  For example, the county road 2 miles south of the county center point would be County Road 200S, while one 3 miles east of that would be County Road 300E.  It works much better in the farming areas in the northern half of the state than the hilly southern half.

[Max Rockatansky]

The main problem with the lettered county route system in California is that a lot is that a lot of counties don't participate in it.  A lot of what Tulare County was going for with their truck load of designations would have made a lot more sense if Kern County actually participated.  Secondarily the actual field signage standards vary from just okay to close to non-existent.

[ClassicHasClass]

And then there are secondary routes in some California counties (Lassen comes to mind).

[Max Rockatansky]

And then there are secondary routes in some California counties (Lassen comes to mind).

Tulare and Kern Counties both have their own Mountain Route system.  They even have route designations which can be seen on Postmile paddles similar to what Caltrans uses.

[TheCatalyst31]

*Illinois?

Illinois has "hidden" highway numbers on state-maintained roads that aren't part of a signed numbered highway. I put hidden in quotes because the highway numbers are still visible on their mile markers, like so:

The numbering convention is a bit odd; there's a clump of numbers in the 900s, a clump in the 8000s, and a few other scattered numbers.

Indiana and Wisconsin both have mileage caps, so I imagine they usually try to foist minor highways on the county or municipality. In Wisconsin at least, there's no real intermediate step between silly minor state highways with normal numbers and stuff the state doesn't maintain, and stuff like tiny connectors don't get their own numbers.

[Rothman]

Got this from an operations engineer at IDOT when I was asking about the circle signs referencing a route 316:

"Thank you for your inquiry regarding mile marker reference signs.  IDOT uses a specific type of mile marker sign (below) for non-Interstate highways to aid in identifying crash locations and to provide general reference information.

The reference sign has a square green background containing a white circle with a legend that conveys three pieces of information: The top line gives the route number of the State highway.  If the route is unmarked, then an alternate or arbitrarily assigned 900-series number is used.  The middle line shows the county name, and the bottom line gives the mileage from the west or the south county line.

While the route near Charleston is not officially designated as state route 316, this is what our local IDOT district and residents in the area refer to the road as, so 316 was chosen for display on the reference signs."

[NE2]

I guess this is now about county routes. Any mention of the actual topic will be met with goats.

[KeithE4Phx]

Got this from an operations engineer at IDOT when I was asking about the circle signs referencing a route 316:

"Thank you for your inquiry regarding mile marker reference signs.  IDOT uses a specific type of mile marker sign (below) for non-Interstate highways to aid in identifying crash locations and to provide general reference information.

The reference sign has a square green background containing a white circle with a legend that conveys three pieces of information: The top line gives the route number of the State highway.  If the route is unmarked, then an alternate or arbitrarily assigned 900-series number is used.  The middle line shows the county name, and the bottom line gives the mileage from the west or the south county line.

I lived in Illinois for 19 years (1975-94), all in the Chicago metro area.  I don't remember seeing any sign that looked like that.  Are those something more recent, as in post-1994?  More downstate than in metro Chicago?  The county roads were marked with the standard pentagon County Road sign, but that was it.

[KeithE4Phx]

I guess this is now about county routes. Any mention of the actual topic will be met with goats.

Minor and Primary are opposite.  I have yet to drive in a state that signs things like freeway ramps separately, old routes (other than historic routes like Historic US 66, but they are not official in most cases) and "connector" routes.  There may be some, but most minor routes are maintained by counties.  Missouri's lettered routes and the too-many side roads in Virginia and North Carolina, and those weird routes in West Virginia are exceptions.

[Scott5114]

I have yet to drive in a state that signs things like freeway ramps separately, old routes (other than historic routes like Historic US 66, but they are not official in most cases) and "connector" routes. 

You've never driven in Nevada or New Mexico?

[Mapmikey]

*South Carolina (spur)

South Carolina also has CONN routes in their primary system.  Some are fully posted and some are posted with the standard secondary marker

North Carolina has at least one unposted primary A route that is similar to Virginia Y routes...NC 268A is in North Wilkesboro, here - https://maps.app.goo.gl/osXkLqAK3n243zre9  They used to have more.


The Virginia (frontage) should probably be in the category below the one it is in.  They are in the primary system and their numbering is a separate system unrelated to the state highway/interstate they are associated.  I differentiate that from Oregon which has a LRN and a different posted number on the same road.

SC and WV both used to have Y routes, likely unposted.  SC also used to have a separate P system 1970s-90s which were arterials or bypasses within/around larger towns.  They were signed like secondary routes but with a P instead of S in front of the county indictor and route number.  At least one was promoted to a posted primary route (SC 56/72 bypass of Clinton).  The rest were placed back into the secondary system at some point.  They were on maps:

P-3002 is shown on this Laurens County map

[KeithE4Phx]

I have yet to drive in a state that signs things like freeway ramps separately, old routes (other than historic routes like Historic US 66, but they are not official in most cases) and "connector" routes.

You've never driven in Nevada or New Mexico?

My last trip to Nevada (Vegas and Laughlin) was 2 years ago, and I haven't set foot in New Mexico since 1994, when I moved to Arizona from Illinois.  I don't recall seeing any freeway ramp with a separate number in NV, nor any historic highway in NM other than 66.  I'm 70, so maybe my memory is fading.

[Scott5114]

I have yet to drive in a state that signs things like freeway ramps separately, old routes (other than historic routes like Historic US 66, but they are not official in most cases) and "connector" routes.

You've never driven in Nevada or New Mexico?

My last trip to Nevada (Vegas and Laughlin) was 2 years ago, and I haven't set foot in New Mexico since 1994, when I moved to Arizona from Illinois.  I don't recall seeing any freeway ramp with a separate number in NV, nor any historic highway in NM other than 66.  I'm 70, so maybe my memory is fading.

They both have signed frontage road numbers (NV on the small white mileposts, with "FR" instead of "SR" at the top; NM on a special state-outline shield). Those are both instances of what the thread is about (minor roadways with state maintenance).

[NE2]

Thanks Mapmikey for a few corrections. I had put a few in the wrong category inadvertently.

[flan]

Here are the North Dakota examples I can think of:

The frontage road for I-94 from Exit 328 to Exit 342 is marked as ND 10 on maps but unsigned in the field. I don't know if sections of this frontage road were ever an alignment of US 10 though.

There are two ND 89s and ND 91s, only one of each are signed but they are all very small roads that are essentially spurs or connectors. There is also ND 97, which is a small bypass of Velva. These are seemingly arbitrary besides being high 2-digit numbers; they are also the only ND highway numbers between 73 and 127.

Hopefully this is the type of thing you're looking for. Seems like ND fits in the second category.

[Rothman]

Got this from an operations engineer at IDOT when I was asking about the circle signs referencing a route 316:

"Thank you for your inquiry regarding mile marker reference signs.  IDOT uses a specific type of mile marker sign (below) for non-Interstate highways to aid in identifying crash locations and to provide general reference information.

The reference sign has a square green background containing a white circle with a legend that conveys three pieces of information: The top line gives the route number of the State highway.  If the route is unmarked, then an alternate or arbitrarily assigned 900-series number is used.  The middle line shows the county name, and the bottom line gives the mileage from the west or the south county line.

I lived in Illinois for 19 years (1975-94), all in the Chicago metro area.  I don't remember seeing any sign that looked like that.  Are those something more recent, as in post-1994?  More downstate than in metro Chicago?  The county roads were marked with the standard pentagon County Road sign, but that was it.

Just look at the post above mine...and, like the IDOT ops engineer said, he was referring to state highways, not county routes.

[GaryV]

Michigan (connector and old)

There are connector routes, maybe a half-dozen signed and others not signed. There are also several very short routes with individual numbers, sometimes heading into state parks.

Michigan also has a number of unsigned routes (often old routes bypassed by freeways) that are still maintained by the State.

(I think) Michigan assign county route numbers in a statewide grid

Not most county routes, but the Intercounty system. https://www.michiganhighways.org/county/intercounty.html
Routes are prefixed by letters A-H based on geography. In a few instances the letter changes as the route moves from one area to the next.

Some counties have a number system. Others use a pattern (Mile Roads, Xth Ave/St, letters, even the names of Vice Presidents). Many just have road names.

[1995hoo]

....

The Virginia (frontage) should probably be in the category below the one it is in.  They are in the primary system and their numbering is a separate system unrelated to the state highway/interstate they are associated. ....

For those interested, here's an example from Fairfax County somewhat near Falls Church. US-50 is the main route through there and the sign in the foreground is for the frontage road on the north side of Route 50. The other frontage road on the other side of Route 50 has a different number, though in context it's logical.

[NWI_Irish96]

*Illinois?

Illinois has "hidden" highway numbers on state-maintained roads that aren't part of a signed numbered highway. I put hidden in quotes because the highway numbers are still visible on their mile markers, like so:

The numbering convention is a bit odd; there's a clump of numbers in the 900s, a clump in the 8000s, and a few other scattered numbers.

Indiana and Wisconsin both have mileage caps, so I imagine they usually try to foist minor highways on the county or municipality. In Wisconsin at least, there's no real intermediate step between silly minor state highways with normal numbers and stuff the state doesn't maintain, and stuff like tiny connectors don't get their own numbers.

Indiana is not up against their cap. They foist minor highways on counties and municipalities because they want to.

[Max Rockatansky]

I have yet to drive in a state that signs things like freeway ramps separately, old routes (other than historic routes like Historic US 66, but they are not official in most cases) and "connector" routes.

You've never driven in Nevada or New Mexico?

Outside of Clark County NDOT will even fully sign routes like this.  They even often install a full set of "begin" and "end" placards.