Even/odd rules for cardinal direction

[TheStranger]

So do most states use odd-north/south, even-east/west as the delineator?  I think New York has it reversed (notably with NY 5, NY 17, and NY 22), while some states completely ignore the distinction.

California mostly follows this rule, but there are some notable exceptions:

Route 14 - former US 6 (east-west route with a long north-south segment)
Route 91 - former US 91 of course (southernmost segment of a long north-south highway)
Route 160 and 70 - former Route 24 (longer extent of an east-west route); Route 70 north of Marysville is former US 40A as well (and is signed east-west rougly after Route 191)
Route 299 - former US 299
Route 37 - formerly ran up current Route 121 as a north-south route (the portion east of Sears Point was once Route 48)
Route 371 - former Route 71


And some examples which were not based on historical numberings:
77, 201, 155, 236, 237, 238 (the previous three are all former routings of Route 9), unbuilt 164 and 258, 84 from Rio Vista north (an extension of an existing east-west route), 86 (former US 99), 72, 82, 254 (last three are former routings of US 101), 193

The longest "opposite number" routes probably are 299 and 14.

[corco]

Washington mostly does with a couple of small exceptions (SR 523 is a straight line east-west, SR 531 runs east-west for 85% of its route and then turns north south for the last 15%)
Idaho couldn't care less about the distinction
Oregon does except for some of the post-2002 routes that just use the highway number. 
Utah does not at all
Wyoming doesn't

[mightyace]

I don't think Pennsylvania does, at least, not anymore.
I haven't seen any such pattern in Ohio or Tennessee either.

I'm sure someone will correct me if I'm mistaken. 

[Michael]

I think New York has it reversed (notably with NY 5, NY 17, and NY 22), while some states completely ignore the distinction.

NY 89 and 13 are north-south.  NY 104 and 222 are east-west.

[vdeane]

I think New York numbers are pretty much random.

[Bryant5493]

Georgia's are random, as some the routes change direction (SR 54 is north-south from it's northern beginning at I-75/85 to Tara Boulevard/US 19/41); it then becomes east-west from US 19/41 to around its terminus in Hogansville (?).


Be well,

Bryant

[DrZoidberg]

Oregon's seem pretty random as well.  214 runs north-south, as does 212, 213, 217. 

I think Wisconsin, from when I lived there, is random as well.  78 runs north-south.

WI has a few routes that change direction.  WI-23, WI-100, and WI-22 are such examples.

[US71]

In general, Arkansas follows the N-S Odd, E-W Even. One notable exception is AR 60.  One segment is posted N-S, another E-W.

At one time, AR 45 was E-W in some areas, N-S in others, but in the early 70's changed to all N-S.

I'm not aware of any one road that is strictly opposite of what it should be.  

[Tarkus]

Oregon's seem pretty random as well.  214 runs north-south, as does 212, 213, 217. 

Well, OR-212 runs fairly east-west from what I've seen, but the distinction made a little bit more sense in the past.  212 actually used to run down 82nd Drive, and crossed a bridge in Gladstone that's no longer there.  It then went through West Linn down Willamette Falls Drive and Borland Road, then through Tualatin on 65th, Nyberg and Tualatin Road before terminating at 99W halfway between Tigard and Sherwood.  It was shortened to the current 212 sometime in the 1970s or 1980s after I-205 was built.

OR-213 and OR-217 going north-south makes sense with the odd number endings.  I believe part of OR-213 was OR-215 at one point.  OR-214 is a little weird, though.  The way ODOT has 214 and 219 signed outside of Woodburn there is kind of confusing, and it would actually make a bit more sense to do away with 214 altogether and sign the whole thing as 219.  (I'd also extend the OR-219 designation onto Washington County-maintained Glencoe Road, ala OR-210, and have it terminate in North Plains at US-26.)

The new post-2002 routes can be annoying because of the lack of convention involved . . . it always screws with me to see OR-569 "East" on the Beltline in Eugene--which they've only in the past 3-4 months gotten around to signing.  Even more annoying, though, is the fact that during the I-105/OR-126 concurrency--also in Eugene--ODOT signed the whole thing as "East I-105/OR-126". 

-Alex (Tarkus)

[brad2971]

Colorado, for the most part, does follow the even/odd rules. Two notable exceptions are found in Denver: SH 2 (Colorado Blvd) and SH 88 (Federal Blvd. south of Colfax).  As far as neighboring states go, neither Nebraska nor Kansas follow convention.

OTOH, South Dakota's highway system almost religiously follows the US Highway numbering system. This is despite the fact that SD is one of only two states that does not have a single-digit state highway

[ctsignguy]

Ohio's system is pretty random...

But until the 70s, Ohio was pretty unique in that their directional tabs acknowledged that highways can go in more than 4 directions...routes like US 42 would be signed as N-EAST or S-WEST.....likewise, US 33 was signed as N-WEST or S-EAST.....until the Feds told them to quit it!

[njroadhorse]

New Jersey follows this almost exclusively.  The exceptions are NJ 42 (N-S) and NJ 49 (E-W)

[Chris]

These rules are violated often, even with the US and Interstate Highway system.

For example, the US 20 runs 104 miles due south in Wyoming.
I-25 runs 60 miles due west in Wyoming
US 18 runs 47 miles due north in Wyoming
I-90 runs south for about 110 miles in Montana and Wyoming
I-94 runs south for miles from Milwaukee to Chicago
I-25 runs east in New Mexico for approximatly 100 miles
US 180 runs south for about 200 miles in Arizona and New Mexico
US 54 runs north for about 220 miles between El Paso, TX and Vaughn, NM
I-4 is more like a N-S route through Orlando, FL
I-95 is more like an E-W route through most of Connecticut

[TheStranger]

Chris: Some of those are more "segments of route" rather than the entire route running entirely in a different direction than expected given the last digit...

Then again, that makes me wonder: is I-26 signed north-south in Tennesee?

I wonder if US 66 was signed north-south in Illinois approximately along what is now I-55.

[akotchi]

New Jersey follows this almost exclusively.  The exceptions are NJ 42 (N-S) and NJ 49 (E-W)

New Jersey is not that exclusive, actually.  A few others . . .
NJ 440 is also north-south (at least in Hudson County -- they can't decide in Middlesex)
NJ 3 is east-west
NJ 495 is east-west (though this was an Interstate)
NJ 5 is east-west
NJ 7 goes in all directions, because it is in separate segments
NJ 18 is north-south
NJ 20 is north-south
NJ 208 is north-south
NJ 36 goes in all directions because of its routing
NJ 37 is east-west

[Darkchylde]

Then again, that makes me wonder: is I-26 signed north-south in Tennesee?

East-west, though US 23 is signed north-south through the concurrency.

[Revive 755]

I think Missouri tries to follow the same East-West rules with state highways as the US Highways and Interstates do, at least according to an older version of the driver's manual.  Major exceptions:

* MO 47 (kind of a loop around St. Louis)
* MO 115
* MO 68 (should be a southern extension of MO 89, with MO 28 ending at Belle and MO 28's I-44 to US 63 section numbered as something else)
* MO 102
* MO 7(diagonal that is more E-W than N-S)
* MO 144 (spur into Hawn State Park off of MO 32; should be MO 132)
* MO 376 (short diagonal in the Branson area that appears to be more N-S than E-W; really should be a lettered route)

There's probably a few more I've missed.

[US71]

I think Missouri tries to follow the same East-West rules with state highways as the US Highways and Interstates do, at least according to an older version of the driver's manual.  Major exceptions:

* MO 47 (kind of a loop around St. Louis)
* MO 115
* MO 68 (should be a southern extension of MO 89, with MO 28 ending at Belle and MO 28's I-44 to US 63 section numbered as something else)
* MO 102
* MO 7(diagonal that is more E-W than N-S)
* MO 144 (spur into Hawn State Park off of MO 32; should be MO 132)
* MO 376 (short diagonal in the Branson area that appears to be more N-S than E-W; really should be a lettered route)

In Cassville, MO 112 is posted E-W at times, N-S at other times.

[Alps]

I'm of course going to take great exclusion to the NJ statement.  Routes here are grouped by part of the state, not last digit.
Anyway, Delaware's basic grid is perfectly on the system, in fact matching the US Highway system in principle.  Some of the other borrowed routes like 896 end up being exceptions.
Florida certainly has a good grid system as well, although of course in a state of that size it will get messed up a lot.

[roadfro]

Nevada's routes numbers are determined by route classification and geographic area.

If interested, there's more on this in the state numbering thread...

[akotchi]

I'm of course going to take great exclusion to the NJ statement.  Routes here are grouped by part of the state, not last digit.

Makes much more sense, now that you mention it . . .