Exit 0

[Duke87]

[This thread has been split from the Southern GSP observations thread in the Northeast section of the the forum and then moved here. -S.]

How often does an Exit 0 happens? I remember a few, like Exit 0 on I-10 in Texas and Exit 0 near Sioux Falls on I-229.

Add I-69 in Indiana to that list.

Theoretically, it should happen whenever an exit is less than half a mile from the beginning of the route. In practice, many DOTs instead opt to fudge it and call it exit 1 in such cases. California, for instance, by policy always does that.
Why? "Driver expectation". There being an exit 0 confuses some people, somehow. I don't get where it's confusing, but there you have it.

[agentsteel53]

there is even an Exit 00 somewhere (Texas?  I forget) where apparently there were exits 0 and 1 and they wanted to fit one inbetween but didn't want to call it 0A.  Or something like that.  Maybe it was even before 0, and they didn't want exit -1.

[mefailenglish]

I-164 in Evansville, IN has a posted Exit 0.

[City]

Instead of numbering the last exit "0", they shouldn't even be numbered at all. Maybe many DOTs would oppose it, but it would be less confusing than an exit 0.

[rawmustard]

Instead of numbering the last exit "0", they shouldn't even be numbered at all. Maybe many DOTs would oppose it, but it would be less confusing than an exit 0.

Now why would it be confusing? An interchange at the very start of a route is at the 0 milemarker, and so its number should correctly be 0. One thing that always annoys me about MDOT and I-194 was that the exit at the very start for I-94 was numbered 1. Then you had the exit for Columbia Avenue which is two miles away, but the exit number only increments by one, since the latter exit is numbered correctly based on its milepost. Since the idea of mileage-based exits is to give drivers a way to estimate mileage between interchanges, having Exit 1 where it should be Exit 0 mucks up that process. Perhaps MDOT might consider that when those signs are up for replacement, but I wouldn't hold my breath. MDOT pretty much skirted the issue with M-6, as neither of its termini interchanges are numbered, but at least the first interchange at 8th Avenue is Exit 1, since it's closer to one mile than two from I-196.

Now with sequential exits, it would be wrong for there to be an Exit 0, since you don't count a 0th item when counting sequentially.

[vdeane]

I'm of the opinion that termini interchanges shouldn't be numbered, though that may be influenced by the fact that NY doesn't do it.

[Scott5114]

there is even an Exit 00 somewhere (Texas?  I forget) where apparently there were exits 0 and 1 and they wanted to fit one inbetween but didn't want to call it 0A.  Or something like that.  Maybe it was even before 0, and they didn't want exit -1.

The only 00 I remember seeing was in Puerto Rico.

Oklahoma doesn't use Exit 0, they fudge it by letting Mile 1 for exit numbering last from MP 0.00 to 1.99. Check out this example from I-240 in OKC:

No.	Mi.	Name
1A	0.0	I-44 west — Lawton
1B	0.5	May Ave.
1C	1.5	Penn Ave.
2A	2.4	Western Ave.

Now with sequential exits, it would be wrong for there to be an Exit 0, since you don't count a 0th item when counting sequentially.

In computer programming, array indexes generally start with 0. Therefore many programmers will start numbered lists with 0. If you ever see anyone do this, chances are they're a programmer.

[SSOWorld]

Now with sequential exits, it would be wrong for there to be an Exit 0, since you don't count a 0th item when counting sequentially.

Unless you were a computer scientist

[Hellfighter]

It would be more correct if they put like "Exit .2"! 

[Bryant5493]

I-10 at the southern end of I-65 is numbered exit "0," for the "control cities" of Mississippi and Florida.


Be well,

Bryant

[PAHighways]

The southern terminus of PA Turnpike 66 is marked with 0s:

EXIT 0A - I-70/I-76/PA TPK
EXIT 0B - US 119 NORTH

[SP Cook]

On I-70 in WV, Wheeling Island is exit zero, and is followed eastbound by exit 1 and exit 2, so they could not "fudge" and just call it exit one.

As the name implies, Wheeling Island is an island in the middle of the Ohio River, in WV jurisdiction (the Ohio belongs to WV and KY to the opposite shore, unlike most rivers which are split down the middle). 

[SSOWorld]

The Indiana Toll road interchange with US 12/20/41 where it becomes the Chicago Skyway is Exit 0.

[Mr_Northside]

The southern terminus of PA Turnpike 66 is marked with 0s:

EXIT 0A - I-70/I-76/PA TPK
EXIT 0B - US 119 NORTH

Wasn't there a period of time that the Arona Rd. exit was #0.  (Sometime right after the switch to mileage based, but before the US-119 cloverleaf became exit 0)??
Or is my mind just playing tricks on me.

[PAHighways]

Wasn't there a period of time that the Arona Rd. exit was #0.  (Sometime right after the switch to mileage based, but before the US-119 cloverleaf became exit 0)??
Or is my mind just playing tricks on me.

I only remember it as 2 before the conversion.

[myosh_tino]

Oklahoma doesn't use Exit 0, they fudge it by letting Mile 1 for exit numbering last from MP 0.00 to 1.99. Check out this example from I-240 in OKC:

No.	Mi.	Name
1A	0.0	I-44 west — Lawton
1B	0.5	May Ave.
1C	1.5	Penn Ave.
2A	2.4	Western Ave.

AFAIK, There will be no "Exit 0" in California.  They fudge Mile 1 similar to what Oklahoma does in the quoted section above but it's a little different...

Mile 1 zone = 0.00 to 1.49
Mile 2 zone = 1.50 to 2.49
Mile 3 zone = 2.50 to 3.49
and so on.

For example...

Exit #	Mileage	Name
1A	0.50 mi	Coleman Avenue
1B	1.25 mi	North 1st Street
2A	1.75 mi	U.S. 101 Southbound
2B	2.00 mi	U.S. 101 Northbound
3	3.25 mi	Brokaw Road

[vdeane]

That would still be in the exit 1 range even if CA used exit 0.

Most exit 0 issues could probably be eliminated if termini were not numbered.

[mightyace]

That would still be in the exit 1 range even if CA used exit 0.

Most exit 0 issues could probably be eliminated if termini were not numbered.

In the sequential numbering days, PA's interstate to interstate junctions did not have exit numbers with the exceptions of the PA Turnpike and of I-180 & I-80, but that is because I-180 West used to be PA 147 North.

Even though I like sequential numbering, I always thought that was odd. 

Not surprisingly, they got exit #s with the move to mileage based exits, one of the few things that I like about the change.

[agentsteel53]

Vermont, if I recall correctly, does the same thing.  The I-93 exit on I-91 does not have a number.  Exit 21 is to the north of it, and exit 20 to the south.  I remember once missing my exit thinking "oh, it's two exits away, I will look out for exit 19".  Nope! 

[froggie]

I-93 doesn't have an exit number there, but I-91 does.  Exit 19.

Of the six cases of Interstate route junctions in Vermont (3 junctions with 2 routes each), the three that do not have exit numbers are the above-mentioned I-93, I-189 at its I-89 terminus, and I-89 where it crosses I-91 (exit number on I-91 there is 10N/S).

[Mike_OH]

On I-75 in Cincinnati, there exits 1A, 1B, 1C, 1D, 1E, 1F, and 1G within the first mile.  Plus, Exit 2A comes at the 1.5 mile marker.

[Darkchylde]

I-110 in Louisiana has too many Exits 1 - from south to north - 1I-J (Terminus), 1A, 1B, 1C, 1H, 1D, 1G, 1E and 1F (yes, in that order.)

Only Exit 0 I've ever seen was the one on I-40 in Texas. And even then they're hit or miss - I-45 doesn't have any Exits 0, but has at least one exit that'd probably qualify.

[deathtopumpkins]

I-110 in Louisiana has too many Exits 1 - from south to north - 1I-J (Terminus), 1A, 1B, 1C, 1H, 1D, 1G, 1E and 1F (yes, in that order.)

I-70 in Kansas City has an exit 2A-Z I believe...

[agentsteel53]

I-70 in Kansas City has an exit 2A-Z I believe...

except for O and I, yes.  But the exits are not all on I-70.  They are all on this monster loop road that is 70 for part of the route, but not all. 

http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=kansas+city+MO&sll=37.0625,-95.677068&sspn=47.215051,70.664062&ie=UTF8&hq=&hnear=Kansas+City,+Jackson,+Missouri&ll=39.102391,-94.582844&spn=0.022746,0.050855&z=15

incidentally, 70 westbound is damn near impossible to follow for the first-time traveler.  I wonder why they didn't just route 70 on the route that is now 670 - it's not only shorter, but straighter as well.

[Greybear]

I-70 in Kansas City has an exit 2A-Z I believe...

except for O and I, yes. 

Z isn't used either.

There is an Exit 0 on I-10 at the Texas/New Mexico line.