Do exit numbers really always need to reset at state lines?

[oscar]

US 93 (and the new I-11) reset at the Arizona-Nevada line over the Hoover Dam, but Arizona has it mileposted as an east-west route. This means there are two Exit 2s about 4 miles apart, one on either side of the line.

Ditto for the Trans-Canada Highway at the QC/MB border. QC treats its part (A-85) as north-south even though it really isn't, while NB's part (NB 2) is west-east. So you have separate exit 1s on both sides of the border.

[Thing 342]

Have found it interesting that the Capitol Beltway does not reset, but nearby I-295 and I-395 do (I'm assuming it's to keep the numbers on 495 from jumping three times). 295 being especially interesting, as the southern terminus in Maryland at I-495 is marked as Exit 1, followed by another Exit 1 (at Laboratory Road) after you enter DC.

Another case of this is the St. Louis Outerbelt, where I-270 resets when it crosses the Mississippi, but I-255 doesn't.

[vdeane]

Ditto for the Trans-Canada Highway at the QC/MB border. QC treats its part (A-85) as north-south even though it really isn't, while NB's part (NB 2) is west-east. So you have separate exit 1s on both sides of the border.

In this case, one could argue that those are both parts of the same interchange split by the provincial line.

[CNGL-Leudimin]

US 93 (and the new I-11) reset at the Arizona-Nevada line over the Hoover Dam, but Arizona has it mileposted as an east-west route. This means there are two Exit 2s about 4 miles apart, one on either side of the line.

This is due to Arizona choosing former US 466 over US 93. Both routes overlapped from the Nevada border to Kingman, where US 466 ended. Otherwise they sign US 93 as North-South.

[1995hoo]

The Capital Beltway (I-495) does not reset.

Resets at the southern Potomac River crossing.

Does not reset at the northern Potomac River crossing (you did mention that).

I feel that's a little hypertechnical compared to the point I was making. Of course the numbers have to restart somewhere. My point was that they originally started, and now once again start, at one location and do a full circle without resetting (though for around 20 years they did reset partway around). I think I view the Wilson Bridge area as more of a "zero point"  rather than putting significance on the state/district line because the Old Town Exit used to be Exit 1 and that number worked as a point of origin for both Virginia's sequential numbers and Maryland's mile-based (the latter because Maryland's first exit east of there was Exit 2).

[US 89]

US 93 (and the new I-11) reset at the Arizona-Nevada line over the Hoover Dam, but Arizona has it mileposted as an east-west route. This means there are two Exit 2s about 4 miles apart, one on either side of the line.

This is due to Arizona choosing former US 466 over US 93. Both routes overlapped from the Nevada border to Kingman, where US 466 ended. Otherwise they sign US 93 as North-South.

No, 93 is signed north-south the whole way. It's mileposted as if it were an east-west route for its entire distance in AZ, all the way to Wickenburg. The portion of 93 past Kingman was never 466.

Source

[Beltway]

I feel that's a little hypertechnical compared to the point I was making. Of course the numbers have to restart somewhere. My point was that they originally started, and now once again start, at one location and do a full circle without resetting (though for around 20 years they did reset partway around). I think I view the Wilson Bridge area as more of a "zero point"  rather than putting significance on the state/district line because the Old Town Exit used to be Exit 1 and that number worked as a point of origin for both Virginia's sequential numbers and Maryland's mile-based (the latter because Maryland's first exit east of there was Exit 2).

There have been four different numbering schemes, and at one point three unrelated exit numbering schemes.

Looking over what I wrote in 2007 --
http://www.capital-beltway.com/Capital-Beltway-History.html#Exit-Numbering

[GaryV]

I've always thought if a route was less than 1000 miles in total length, there's no need to reset at every state line, especially in the Northeast, where states are smaller. However, four-digit exit numbers should be avoided.

The problem with that is, if the state at the 0-mile end decides to extend the road, all the other states have to renumber.

[jp the roadgeek]

I-275 OH/IN/KY does not reset at any state line; it has the same mileposts throughout.

I just assume that I-84 not reset at the MA state line.  It's basically a 7.8 mile connection to the Mass Pike from CT.

I-684, while it doesn't have any exits in CT, maintains NY mileposts.  Same with the brief NY 17 dip into PA.

I-76 in NE doesn't number the exit at its junction with I-80.  It does, however, switch from E-W in CO to N-S in NE

I-59 in LA is so short (11.48 mi) it might as well not reset at the MS border.

[mrcmc888]

The short segment of I-24 in Georgia uses the Tennessee exit numbers.

It is also maintained by TDOT, so it makes sense.

[SD Mapman]

I-76 in NE doesn't number the exit at its junction with I-80.  It does, however, switch from E-W in CO to N-S in NE

NE uses the convention that the junction interstate determines the exit number, hence although the mileposts reset at the state line (and go up to 2 in NE) the exit is numbered 102.

[US 89]

I-76 in NE doesn't number the exit at its junction with I-80.  It does, however, switch from E-W in CO to N-S in NE

NE uses the convention that the junction interstate determines the exit number, hence although the mileposts reset at the state line (and go up to 2 in NE) the exit is numbered 102.

So that exit is 102 because I-80 is at mile 102 there. Weird.

And in any case, I-76 wouldn’t be an example of not resetting at a state line. If Nebraska continued Colorado’s mileposts, that exit would be numbered 187.

And I never realized 80 was a TOTSO at that junction, either. 76 is set up as the mainline.

[cjk374]

The short segment of I-24 in Georgia uses the Tennessee exit numbers.

It is also maintained by TDOT, so it makes sense.

Maintained by TnDOT, uses Tennessee exit numbers, but mileposted for GA.

https://www.google.com/maps/@34.9726788,-85.4208789,0a,75y,213.68h,91.56t/data=!3m4!1e1!3m2!1suT_5eiym0Ck1J4MT7xK3Cw!2e0

The link starts at the exit 167 advance warning sign. Scroll forward to just past the speed limit 70 sign and you will see MP 3. Also noteworthy:  1. GSV labels I-24 as GA 409.  2. The I-24 reassurance assemblies are non-neutered Georgia shields.

______________________________________________________________________________________________________________


Quote from sparker: 

I know of no instance where RR mileposts reset at state lines; being private companies, there was no need to do that in any case.

The part of KCS's "Meridian Speedway" from Meridian to Shreveport was once part of the Illinois Central (before that the Vicksburg, Shreveport & Pacific). MP 0 is Meridian, and runs to MP 140.6 to the MS River bridge at Vicksburg. The mileposts then reset at the MS/LA state line and run MP 0 to MP 172.something where the mainline meets the original KCS north-south mainline going to Deramus yard. I have no idea why VS&P reset the mileposts like that, but it has always been that way.

[jp the roadgeek]

And then there's the curious case of RI 146, whose numbers do reset at the MA line, but have mileposts that go up in both directions.  Northbound starts at 0 heading north and west from I-95, while southbound goes up from 0 from the MA border.  Hope the planned numbering of the exits based on MUTCD mileage based standards fixes this. 

[Roadwarriors79]

I-76 in NE doesn't number the exit at its junction with I-80.  It does, however, switch from E-W in CO to N-S in NE

NE uses the convention that the junction interstate determines the exit number, hence although the mileposts reset at the state line (and go up to 2 in NE) the exit is numbered 102.

So that exit is 102 because I-80 is at mile 102 there. Weird.

And in any case, I-76 wouldn't be an example of not resetting at a state line. If Nebraska continued Colorado's mileposts, that exit would be numbered 187.

And I never realized 80 was a TOTSO at that junction, either. 76 is set up as the mainline.

I-76 was once I-80S there, so that TOTSO makes sense.

[Eth]

Also noteworthy:  1. GSV labels I-24 as GA 409.

Google Maps shows most of these unsigned state routes on the Interstates, though for some reason appears to omit them from I-20 (402) and I-285 (407).

[Bruce]

Exit numbers on 3dis really shouldn't need to reset, especially when serving a multi-state metro area.

I-205 in Portland, OR and Vancouver, WA carries over its exit numbers, for example.

https://www.wsdot.wa.gov/Traffic/InterstateGuide/205.htm

[SGwithADD]

I-86 at the NY-PA border does not reset.  This has the oddity of transitioning from mileage-based exits to sequential exits without resetting.  The first NY exit, less than a mile east of the border, is Exit 4 for NY 426.  I believe this is a remnant from the pre-86 days, when the Pennsylvania part of the route was numbered PA 17 (for continuity with NY 17).

[vdeane]

Possibly sheer coincidence (the original continuous scheme was with PA sequential using exit 2; I'm not sure what exit 3 was supposed to have been), though the fact that it's near milepost 4 makes me wonder if PA deliberately went down a number to avoid duplicating NY.  Also makes me wonder what NY would do if it ever went mile-based.  Follow the mileposts (which are not continuous), with the exit numbers going 1A/B-3-1, or leave the first exit as 4 even though it's a couple miles off?

[jp the roadgeek]

Another curious case would be if I-278 added exit numbers in NJ.  According to Wikipedia, they have or plan to, and will us 3A-3B-3C as the numbers, while the first exit on the Staten Island side is 3.  If NJ used the correct mileposts, and NY went to mileage based, you'd have 1A-1B-1C on the NJ side, then a possible 1A-1B-1C-1D on the NY side (I see NY rounds down even if over the xx.50 MP). 

[stwoodbury]

The Capital Beltway (I-495) does not reset. It has a convoluted exit number history. Originally the exits were numbered clockwise (per federal standards for a loop route) from Exit 1 in Virginia to Exit 38 in Maryland. A few years after I-95 was moved to the eastern side of the Beltway, Maryland changed to milepost numbers and set theirs starting at Exit 2; I-495 then inherited I-95's and continued up to Exit 41. The numbers ran (and still run) anti-clockwise because I-95 bring a 2di trumped the loop route. Virginia didn't change to milepost numbers until some years later and when they did, they initially didn't change the Beltway. Eventually they decided to continue Maryland's numbers down to the Springfield Interchange (adding Exits 43 to 57), but then the remaining eight miles got Virginia I-95 exit numbers because I-95 trumps I-495. This confuses the crap out of many people because driving straight ahead on the same road Exit 57 is followed by Exit 173!

I don't understand why 95 and 495 run together on the eastern half of the Beltway while 495 also runs on the western side. Why isn't 95 the eastern half and 495 the western half? That never made sense to me.   


iPad

[jp the roadgeek]

The Capital Beltway (I-495) does not reset. It has a convoluted exit number history. Originally the exits were numbered clockwise (per federal standards for a loop route) from Exit 1 in Virginia to Exit 38 in Maryland. A few years after I-95 was moved to the eastern side of the Beltway, Maryland changed to milepost numbers and set theirs starting at Exit 2; I-495 then inherited I-95's and continued up to Exit 41. The numbers ran (and still run) anti-clockwise because I-95 bring a 2di trumped the loop route. Virginia didn't change to milepost numbers until some years later and when they did, they initially didn't change the Beltway. Eventually they decided to continue Maryland's numbers down to the Springfield Interchange (adding Exits 43 to 57), but then the remaining eight miles got Virginia I-95 exit numbers because I-95 trumps I-495. This confuses the crap out of many people because driving straight ahead on the same road Exit 57 is followed by Exit 173!

I don't understand why 95 and 495 run together on the eastern half of the Beltway while 495 also runs on the western side. Why isn't 95 the eastern half and 495 the western half? That never made sense to me.   


iPad

Because the entire Beltway was I-495 before I-95 was placed on it once I-95 inside the Beltway was killed north of the Capitol area (the built portions becoming I-395).  It's basically there as a legacy much like MA 128 remains on I-95 outside of Boston after I-95 was moved there once the Northeast Expressway was killed.

[abefroman329]

The Capital Beltway (I-495) does not reset. It has a convoluted exit number history. Originally the exits were numbered clockwise (per federal standards for a loop route) from Exit 1 in Virginia to Exit 38 in Maryland. A few years after I-95 was moved to the eastern side of the Beltway, Maryland changed to milepost numbers and set theirs starting at Exit 2; I-495 then inherited I-95's and continued up to Exit 41. The numbers ran (and still run) anti-clockwise because I-95 bring a 2di trumped the loop route. Virginia didn't change to milepost numbers until some years later and when they did, they initially didn't change the Beltway. Eventually they decided to continue Maryland's numbers down to the Springfield Interchange (adding Exits 43 to 57), but then the remaining eight miles got Virginia I-95 exit numbers because I-95 trumps I-495. This confuses the crap out of many people because driving straight ahead on the same road Exit 57 is followed by Exit 173!

I don't understand why 95 and 495 run together on the eastern half of the Beltway while 495 also runs on the western side. Why isn't 95 the eastern half and 495 the western half? That never made sense to me.   


iPad

Because the entire Beltway was I-495 before I-95 was placed on it once I-95 inside the Beltway was killed north of the Capitol area (the built portions becoming I-395).  It's basically there as a legacy much like MA 128 remains on I-95 outside of Boston after I-95 was moved there once the Northeast Expressway was killed.

Except the eastern half was 95 and the western half was 495, for a period after 95 in DC was cancelled.

[1995hoo]

^^^^

People complained that they found it too confusing for a beltway to have split numbering like that, so eventually I-495 was posted again on the eastern side. I've sometimes thought it should have been I-95E and I-95W, though I recognize the reasons why they want thru traffic to use the eastern side.

[abefroman329]

Wikipedia says it was re-posted in 1989, although I could've sworn we took a road trip there in 1990 or 1991 and the eastern half was still only I-95.  Maybe we just had an old road atlas.