Only in these two states...

[kurumi]

Has anyone built a scorigami-style matrix of the 1,225 possible two-state combinations?

AL and MA: have erected signs for AL state route 10
NH and VT: have more than one 2-digit interstate, but they are all odd-numbered

[froggie]

Texas and Missouri:  Only states that extensively marks exit numbers as a tab above the gore sign, on a separate sign as opposed to on the gore sign itself.  I know it shows up in a lot of states, but I have only seen it widespread in those two.

Does Alabama no longer do this?  Used to be widespread there, but I haven't been to the state in 12 years.

[dlsterner]

Arizona and California:  Only states to have a section of a highway or highways where the carriageways cross over and mimic driving on the left side of the road due to the grade of a mountain pass.

I-85 in North Carolina does this briefly as well, although you may not notice it (it took me a few times driving that stretch before I noticed).  Although not because of a mountain pass.

And if you want to get picky, many states are re-building interchanges as DDI (diverging diamond interchange) which reverses the carriageways, albeit briefly.

[SkyPesos]

Kind of surprised this one hasn't been mentioned yet:
Delaware and Maine: Only 2 states with exactly 1 2di, both being I-95.

[Scott5114]

Arizona and California:  Only states to have a section of a highway or highways where the carriageways cross over and mimic driving on the left side of the road due to the grade of a mountain pass.

I want to say Tennessee has one too, but I may be wrong. Of course carriageways cross over and you drive on the left at every diverging diamond interchange.

Texas and Missouri:  Only states that extensively marks exit numbers as a tab above the gore sign, on a separate sign as opposed to on the gore sign itself.  I know it shows up in a lot of states, but I have only seen it widespread in those two.

I think Wyoming does this too.

I was going to say that Colorado and Texas were the only 2 states to refer to their state highways as SH-xx, but it turns out Idaho does too.

So does Oklahoma.

[wriddle082]

Arizona and California:  Only states to have a section of a highway or highways where the carriageways cross over and mimic driving on the left side of the road due to the grade of a mountain pass.

I want to say Tennessee has one too, but I may be wrong. Of course carriageways cross over and you drive on the left at every diverging diamond interchange.

I am not aware of this occuring anywhere in Tennessee, other than in GSMNP where US 441 goes in a complete circle and crosses over itself completely.  But in North Carolina this happens on I-85 b/w Lexington and Thomasville, and on I-77 at the I-85 interchange in Charlotte.

Texas and Missouri:  Only states that extensively marks exit numbers as a tab above the gore sign, on a separate sign as opposed to on the gore sign itself.  I know it shows up in a lot of states, but I have only seen it widespread in those two.

I think Wyoming does this too.

Virginia and West Virginia also do this, but only when the exit number is 3 characters or greater.  So for every three-digit exit, or two-digit exit with a letter suffix.  I'd call that pretty widespread.

Here is my own contribution:  New York and South Carolina are the only two states that don't quite push the exit tabs on BGS's all the way to the left or the right.  They account for the rounded white border of the main sign, and have them so they aren't over the curve.  And I want to say Nebraska might do this as well, but I have only seen photos, and haven't been in that state in over 20 years.

[Bruce]

Washington and Hawaii: Only states where signed state highways were destroyed by volcanic eruptions in living memory. In WA's case, that was State Route 504 near Mt. St. Helens in 1980 (largely taken out by the lahar) and for HI, plenty of choices on the Big Island, among them Routes 130 and 132 from lava flows in the past few years.

(I don't believe any Alaskan highways have been affected in their recent volcanic activity, and the likes of Oregon and Wyoming haven't seen violent volcanic activity in a long time.)

[hotdogPi]

Kind of surprised this one hasn't been mentioned yet:
Delaware and Maine: Only 2 states with exactly 1 2di, both being I-95.

Nobody mentioned it because Rhode Island.

[Flint1979]

Kind of surprised this one hasn't been mentioned yet:
Delaware and Maine: Only 2 states with exactly 1 2di, both being I-95.

Nobody mentioned it because Rhode Island.

If the western I-76 didn't end 3 miles into Nebraska there'd be another state the only other 2-di being I-80.

[oscar]

Washington and Hawaii: Only states where signed state highways were destroyed by volcanic eruptions in living memory. In WA's case, that was State Route 504 near Mt. St. Helens in 1980 (largely taken out by the lahar) and for HI, plenty of choices on the Big Island, among them Routes 130 and 132 from lava flows in the past few years.

For Hawaii, 132 is a county route, as is 137 which is still partially closed. 130 definitely qualifies, with multiple closures (the most recent one has been fixed, but the ones from the 1990s mostly haven't been).

Another Hawaii highway has been trashed by lava, but the closure that comes to mind was in the 1950s, before Hawaii became a state and also before it started using (except temporarily, just on Oahu during World War II) route markers. 

[bassoon1986]

Louisiana and Minnesota, the only two states with capital cities on the Mississippi River.


iPhone

[SkyPesos]

Kind of surprised this one hasn't been mentioned yet:
Delaware and Maine: Only 2 states with exactly 1 2di, both being I-95.

Nobody mentioned it because Rhode Island.

If the western I-76 didn't end 3 miles into Nebraska there'd be another state the only other 2-di being I-80.

I-29 could've been routed between Nebraska City and Sioux City via US 75 too instead of bypassing it on the east; then the state will have a N-S interstate 

[EpicRoadways]

Minnesota and New Jersey: The only two states that still install traffic signals on truss-arms (at least at the state level).

[jeffandnicole]

Minnesota and New Jersey: The only two states that still install traffic signals on truss-arms (at least at the state level).

Definitely on the county/local level in NJ still.

[TheGrassGuy]

NJ's is completely wrong.

[webny99]

ARGUMENT TIME
Which two states' panhandles actually deserve to be called panhandles?

Florida and Oklahoma. Is there even more than two options?

West Virginia's eastern panhandle.

Also Texas, though the region containing El Paso makes more sense to be called a "panhandle" than the Amarillo portion that is the official panhandle.

And I suppose Maryland. But none of Maryland, Texas or West Virginia are shaped like a pan. To me Florida is more pan-shaped - in terms of both the pan and the handle - than West Virginia.

[webny99]

What is a "bump" ?

Where Route A and Route B meet and swap alignments. For example, Route A comes from the north and turns east at the intersection. Route B comes from the west and turns south.

Thanks for giving the real answer before I could say "when you post to a thread that hasn't been posted to in multiple years".

[Revive 755]

Texas and Missouri:  Only states that extensively marks exit numbers as a tab above the gore sign, on a separate sign as opposed to on the gore sign itself.  I know it shows up in a lot of states, but I have only seen it widespread in those two.

Does Alabama no longer do this?  Used to be widespread there, but I haven't been to the state in 12 years.

Iowa used to as well.
Example on I-80.
Former example on I-29.

Maybe someone should make a comment for the new MUTCD asking for this practice to be fully allowed again?

[csw]

Washington and Oregon: centered exit tabs.

I'm not aware of other states that center their exit tabs. WA uses full-width internal exit tabs*, whereas Oregon uses actual tabs mounted above the sign, but both centrally-mount the legend and, in the case of Oregon, the actual tab itself.

This used to be common practice in Missouri in the button copy era, although they no longer do so.

Older BGSs in Connecticut have centered exit tabs as well. See I-95 east of New Haven.

[jakeroot]

Washington and Oregon: centered exit tabs.

I'm not aware of other states that center their exit tabs. WA uses full-width internal exit tabs*, whereas Oregon uses actual tabs mounted above the sign, but both centrally-mount the legend and, in the case of Oregon, the actual tab itself.

This used to be common practice in Missouri in the button copy era, although they no longer do so.

Older BGSs in Connecticut have centered exit tabs as well. See I-95 east of New Haven.

I had included CT in my mention of centered exit tabs upthread. I was thinking they may have been the third state still using centered exit tabs, but I found a bunch of right/left justified exit tabs at the 91/95/34 interchange that confirmed, to me, that they were no longer using them. Any idea when they stopped using them? Seems like a ton of centered exit tabs still exist around CT.

[ilpt4u]

Louisiana and Minnesota, the only two states with capital cities on the Mississippi River.


iPhone

Illinois used to be in that club - and now, the 1st Illinois State capital city is on the west side of the Mississippi River: Kaskaskia (not much left on Kaskaskia Island, anymore, either)

[ran4sh]

Here is my own contribution:  New York and South Carolina are the only two states that don't quite push the exit tabs on BGS's all the way to the left or the right.  They account for the rounded white border of the main sign, and have them so they aren't over the curve.  And I want to say Nebraska might do this as well, but I have only seen photos, and haven't been in that state in over 20 years.

I had already mentioned that above, but I had no idea anyone else had noticed that practice.

[jakeroot]

Here is my own contribution:  New York and South Carolina are the only two states that don't quite push the exit tabs on BGS's all the way to the left or the right.  They account for the rounded white border of the main sign, and have them so they aren't over the curve.  And I want to say Nebraska might do this as well, but I have only seen photos, and haven't been in that state in over 20 years.

I had already mentioned that above, but I had no idea anyone else had noticed that practice.

I didn't see that post but I'm glad someone else brought it up. I've designed more than a few fake signs in my life, and I've always enjoyed this practice of scooting the exit tab in a bit to align with the larger corner radius of the sign it's attached to. Florida and North Carolina would be two places I'd like to see adopt this practice, as they also use rounded corners like New York but float their exit tabs several inches above the sign, a bit like Oregon.

[jeffandnicole]

NJ's is completely wrong.

How so?

[Flint1979]

Louisiana and Minnesota, the only two states with capital cities on the Mississippi River.


iPhone

The slightly longer Missouri River has Jefferson City, Pierre and Bismarck. It also flows within 10 miles of Helena.