States with the most Interstate Crossings

[webny99]

1. NY has 14 total interstate crossings to other states, plus 2 international crossings (I-81, I-190) that don't count for this.

I was unaware of I-87 being truncated.

Make that at least two international crossings.   

Fixed.

[Crown Victoria]

How about Tennessee:


Kentucky: I-24, I-65, I-75 (3) plus 1 future (I-69) 
Virginia: I-81 (1)
North Carolina: I-26, I-40 (2)
Georgia: I-75, I-24 twice (3)
Alabama: I-65 (1)
Mississippi: I-269, I-55, I-69 (2) I-55 and I-69 are concurrent when crossing the TN/MS line, I-69 does exist in TN in Memphis but is not signed yet.
Arkansas: I-55, I-40 (2)
Missouri: I-155 (1)

15 Interstate crossings total currently. The TN/KY border has 4 crossings if counting I-69. The TN/GA border has 3 crossings due to I-24.

[webny99]

I'll start a leaderboard here. Multiplexed routes in a single crossing are separately counted for this. Future crossings, like I-49 AR-MO and I-69 KY-IN aren't counted. Interstate designations that dead end at a border doesn't count.

1 - Illinois (21)
2 - Indiana, Missouri (17)
4 - Ohio (16)
5 - Tennessee (15)
6 - New York (11)
7 - Texas (8)
8 - Wisconsin (7)
9 - Minnesota (8)
10 - Michigan (3)

I have 14 for NY. I'm aware you did not count I-86, which I do think should be counted.

We're still off by one, which I think must be I-99. My position is that I-99 should count for NY, but not for PA. NY shouldn't be penalized for PA not completing their portion yet.

[NWI_Irish96]

I don't think multiplexed routes should count for more than 1.

I should have clarified this in the OP.

Personally, I think they should count once for each route, but feel free to make the case.

If you make the crossing once, you are considered to have crossed on both routes. You don't have to be a double crosser to count both routes.

Right, so if you cross on I-80/I-90 from Ohio into Indiana, it would count as both I-80 and I-90 (in other words, it would be counted twice). Wouldn't that be the case here as well?

It's one crossing. There is only one place you can cross on those roads.

[webny99]

... if you cross on I-80/I-90 from Ohio into Indiana, it would count as both I-80 and I-90 (in other words, it would be counted twice). Wouldn't that be the case here as well?

It's one crossing. There is only one place you can cross on those roads.

I'm not disputing that. I'm saying that on travel mapping or a similar site, it would count twice, once for each route. It's really no different than two routes crossing side-by-side, they just happen to be together at that point.

[JayhawkCO]

Colorado just has 5.  One for every state it borders except Oklahoma (and Arizona if you count it).

Chris

[CoreySamson]

Also keep in mind that Texas will have 3 future interstate crossings: I-69 and I-49 twice. And do international borders count? I-69W goes all the way up to the World Trade Bridge in Laredo.

[JCinSummerfield]

Michigan has 3:  I-94 and I-69 to IN; I-75 to Ohio.

The other ends of all 3 connect to a bridge that goes to Ontario.

This has the potential to double, with I-73, I-67 up the west side, and I-41 up to Marquette.  Of course, we will all be pushing up daisies before any of these happen.

[gonealookin]

Nevada has four, plus an Interstate that ends at a state border and will become #5 in the future.

California:  I-15, I-80
Utah:  I-80
Arizona:  I-15 (plus future I-11)

[plain]

Virginia

DC: I-66, I-395

MD: I-95/495, I-495

NC: I-77, I-85, I-95 (I-73*, I-87*, I-785*)

TN: I-81

WV: I-64, I-77, I-81


11 crossings

*3 future crossings, if built and all with NC, will bring the total to 14.

There's also the possibility of I-74 but I didn't include it at all as no one in VA seems to be thinking about it.

[Great Lakes Roads]

Indiana-

IL: I-90, I-80, I-94, I-74, I-70, I-64
KY: I-69*, I-64, I-65, I-265, I-275
OH: I-275, I-74, I-70, I-80, I-90
MI: I-69, I-94
Total: 18 with a future 19

Wisconsin-
MN: I-535, I-94, I-90
IA: none
IL: I-90, I-39, I-94, I-41
MI: none
Total: 7

Minnesota-
ND: I-94
SD: I-90
IA: I-35
WI: I-90, I-94, I-535
Total: 6

North Dakota-
MT: I-94
SD: I-29
MN: I-94
Total: 3

South Dakota-
WY: I-90
ND: I-29
MN: I-90
IA: I-29
Total: 4

Iowa-
IL: I-80, I-74, I-280
MO: I-35, I-29
NE: I-80, I-480, I-680, I-129
MN: I-35
SD: I-29
Total: 11

EDIT: Whoops, I forgot that I-29 enters South Dakota from Iowa!   

[epzik8]

Maryland has:

DE: I-95 (1)
DC: I-95/495, I-295 (2)
PA: I-70, I-81, I-83 (3)
VA: I-495 (1)
WV: I-68, I-81 (2)

Total: 9, which is nowhere near the highest.

[thspfc]

Michigan has 3:  I-94 and I-69 to IN; I-75 to Ohio.

The other ends of all 3 connect to a bridge that goes to Ontario.

This has the potential to double, with I-73, I-67 up the west side, and I-41 up to Marquette.  Of course, we will all be pushing up daisies before any of these happen.

Christmas will be the warmest day of the year in Detroit before there will be an I-73 shield in Michigan.

[achilles765]

Also keep in mind that Texas will have 3 future interstate crossings: I-69 and I-49 twice. And do international borders count? I-69W goes all the way up to the World Trade Bridge in Laredo.

If we really want to think into the future, eventually Texas will (hopefully and supposedly) have the following:
TX/LA: IH 10, IH 14, IH 20
TX/AR: IH 30, IH 49, IH 69, IH 369
TX/OK: IH 35, IH 40, IH 44
TX/NM: IH 10, IH 40

And who knows, maybe we'll also get an IH 27 crossing into OK or NM

[Crown Victoria]

New Jersey's crossings:


Delaware: I-295 (1)
Pennsylvania: I-76, I-676, I-95, I-295, I-78, I-80 (6)
New York: I-287, I-95, I-78, I-278 (4)

Total: 11 

*NJ would have had another NY crossing had I-495 been constructed across Manhattan. Also another NJ/PA crossing (I-895) was planned but not constructed. Finally, I-84 misses New Jersey by just a few feet while crossing between PA and NY.

[SEWIGuy]

South Dakota-
WY: I-90
ND: I-29
MN: I-90
IA: I-90
Total: 4

Iowa-
IL: I-80, I-74, I-280
MO: I-35, I-29
NE: I-80, I-480, I-680, I-129
MN: I-35
Total: 10

For the bolded, I assume you mean I-29 and not I-90.

And then you forgot to include I-29 to SD in your Iowa section.

[The Nature Boy]

I feel like Maine is going to bring up the rear (with the exception of HI and AK, of course). Their own interstate crossing is the I-95 crossing with New Hampshire.

[US 89]

Utah has 6: two to Idaho (15, 84), one to Arizona (15), one to Nevada (80), one to Wyoming (80), and one to Colorado (70).

[ran4sh]

Georgia has 12.

By route:
I-20 and I-85 each cross into AL and SC
I-75 crosses into FL and TN
I-95 crosses into FL and SC
I-24 crosses into TN going both east and west (east to Chattanooga, west to Nashville)
I-59 crosses into AL
I-520 crosses into SC

By state:
GA/FL has I-95, I-75
GA/AL has I-85, I-20, I-59
GA/TN has I-24 twice, and I-75
GA/NC has no Interstate crossing
GA/SC has I-85, I-20, I-520, I-95