Random facts about interstates and US routes

[SkyPesos]

Widest spreads in N/S or E/W primary interstate routes in one state:

E/W:
California: 80 - 8 == 72
Illinois: 94 - 24 == 70

N/S:
Texas: 69 - 27 == 42
Missouri: 57 - 29 == 28
Tennessee: 81 - 55 == 26

I might have missed some.

For US routes:

E-W:
1. Colorado (84-6=78)
2. California (80-6=74)
3. Ohio (68-6=62)

N-S:
Louisiana and Tennessee (79-11=68)

[ethanhopkin14]

I always found it odd that I-35 in Texas replaced US-81.  35 (and 45 being close to it) is a number that's closer to the middle of the grid, which Texas is close to the center, but 81 seems way too far to the west.  I found it odd that in Texas, the grid is already shifted to 81.  Yes, the country is more sparsely populated heading west from US-81, so the grid can get more spaced out in the graduations, but I always felt it was too far shifted.   

Yes the US Highway grid is was very very flawed, while the Interstate grid seemed to try to correct the errors made in the US grid, but the American southwest is one of the areas where the grid seemed to work, but the numbers seemed unnecessarily cramped (and by that I mean the north-south grid starts to run out of numbers even as far east as east Texas). 

I also found it odd that US-87 was in central Texas, yet the next odd number up, US-89 goes east of the Grand Canyon and goes through Utah.   

On another note, Texas is the proud owner of two horrible intrastate grid violators; US-57 and US-96.  Now, while US-57 is basically a continuation of Federal Route 57, US-96 is a mystery as to why it was numbered that way.  The only thing it has going for it is at one point it is south of US-90, but I for the life of me have no idea why it was numbered even although it's a north-south route.  This isn't a fact, since I did no research on it, but are there any other states that have 2 or more US routes that are this level horrible grid violators?  Intrastate would be preferable, but they don't have to be.   

[SkyPesos]

On another note, Texas is the proud owner of two horrible intrastate grid violators; US-57 and US-96.  Now, while US-57 is basically a continuation of Federal Route 57, US-96 is a mystery as to why it was numbered that way.  The only thing it has going for it is at one point it is south of US-90, but I for the life of me have no idea why it was numbered even although it's a north-south route.  This isn't a fact, since I did no research on it, but are there any other states that have 2 or more US routes that are this level horrible grid violators?  Intrastate would be preferable, but they don't have to be.

I know it's not intrastate, but it's worth nothing that US 59 is out of place in the grid, as it's entirely west of US 71. I think I saw in Fictional once to renumber it to US 73, which would make more sense as it's between 71 and 75 most of the way.

With the interstate grid "fixing" the US routes grid, there's one exception I can think of: Wisconsin. All 3 of its N-S interstates (39, 41 and 43) are east of the general line I-55 goes most of its way between New Orleans and St Louis. This happened because IDOT didn't want to extend 55, 57 or 65 to the Wisconsin line from Chicago, so Wisconsin had to find new numbers to use.

[ethanhopkin14]

On another note, Texas is the proud owner of two horrible intrastate grid violators; US-57 and US-96.  Now, while US-57 is basically a continuation of Federal Route 57, US-96 is a mystery as to why it was numbered that way.  The only thing it has going for it is at one point it is south of US-90, but I for the life of me have no idea why it was numbered even although it's a north-south route.  This isn't a fact, since I did no research on it, but are there any other states that have 2 or more US routes that are this level horrible grid violators?  Intrastate would be preferable, but they don't have to be.

I know it's not intrastate, but it's worth nothing that US 59 is out of place in the grid, as it's entirely west of US 71. I think I saw in Fictional once to renumber it to US 73, which would make more sense as it's between 71 and 75 most of the way.

With the interstate grid "fixing" the US routes grid, there's one exception I can think of: Wisconsin. All 3 of its N-S interstates (39, 41 and 43) are east of the general line I-55 goes most of its way between New Orleans and St Louis. This happened because IDOT didn't want to extend 55, 57 or 65 to the Wisconsin line from Chicago, so Wisconsin had to find new numbers to use.

I don't count that.  I look at intermediate interstate this way: If an I-X0 or I-X5 has ended, you treat it like it doesn't exist.  Example, I-210 north of San Bernardino, CA could be numbered I-78 if it were a 2di because by that time in the grid, the only two remaining I-X0 interstates left are I-10 and I-80.  I-40 had just ended, so that frees up all numbers between 10 and 80.  I don't get into that, because if you draw that line in the sand, then I-8, which is 100% in the correct place in the grid being south of I-10 is on a latitude line that if it were transplanted to the east coast at the same point north and south, all of the route would be north of I-10 and most or some of it would be north of I-16 and I-26.

A route only needs to comply to the rules at that given space in the country. Since I-55 is dead (and I-45 and I-65 for that fact) at that point, the Wisconsin interstates can be numbered anywhere between I-35 and I-75 in order to comply. 

The grid isn't perfectly straight lines; they fluctuate. 

[clong]

Widest spreads in N/S or E/W primary interstate routes in one state:

E/W:
California: 80 - 8 == 72
Illinois: 94 - 24 == 70

N/S:
Texas: 69 - 27 == 42
Missouri: 57 - 29 == 28
Tennessee: 81 - 55 == 26

I might have missed some.

N/S
Alabama: 85 - 59 == 26

[GaryV]

I always found it odd that I-35 in Texas replaced US-81.  35 (and 45 being close to it) is a number that's closer to the middle of the grid, which Texas is close to the center, but 81 seems way too far to the west.  I found it odd that in Texas, the grid is already shifted to 81.  Yes, the country is more sparsely populated heading west from US-81, so the grid can get more spaced out in the graduations, but I always felt it was too far shifted.   

Not in 1926 it wasn't.  Look for the 1924 presidential election results.  There were only 113 Electoral College votes from the Great Plains to the Pacific.  The population was skewed greatly to the east of Texas.

[dlsterner]

Widest spreads in N/S or E/W primary interstate routes in one state:

E/W:
California: 80 - 8 == 72
Illinois: 94 - 24 == 70

N/S:
Texas: 69 - 27 == 42
Missouri: 57 - 29 == 28
Tennessee: 81 - 55 == 26

I might have missed some.

N/S
Alabama: 85 - 59 == 26

N/S
Georgia: 95 - 59 == 36

[Dirt Roads]

N/S
Georgia: 95 - 59 == 36

Can of worms alert!
N/S
Georgia: 475 - 59 = 416
E/W
West Virginia:  470 - 64 = 406

Not sure if there are any other 3dis that serve as "primary" interstates.  I wouldn't count the I-495 Capital Beltway, but I might consider the I-495 VVMH in Wilmington, Delaware.  Is the route to Philly more primary than the route to NJTP? 

[SkyPesos]

N/S
Georgia: 95 - 59 == 36

Can of worms alert!
N/S
Georgia: 475 - 59 = 416
E/W
West Virginia:  470 - 64 = 406

Not sure if there are any other 3dis that serve as "primary" interstates.  I wouldn't count the I-495 Capital Beltway, but I might consider the I-495 VVMH in Wilmington, Delaware.  Is the route to Philly more primary than the route to NJTP? 

I-270 in Missouri/Illinois? Even though it's part of a beltway for St Louis, it's shorter than I-70 for through traffic getting through the St Louis area, as I-70 dips to the south, and comes back north. I-70 even continues I-270's mileposts in IL east of its eastern terminus.

[SkyPesos]

Tennessee and Georgia are the only 2 states with 3 x5's interstates.
I-55,65 and 75 in Tennessee.
I-75,85 and 95 in Georgia.

Louisiana has four US x1:s 11, 51, 61 and 71.

Tennessee has five:  11, 31, 41, 51 and 61

The equivalent for US x0's appears to be Illinois - US 20, 30, 40, 50, and 60.

Initially, most of US 12 in WI, IL and MI was originally planned to be part of US 10. Combine that with a much longer US 60 in the state (on what is now US 66), Illinois would have 6 x0 US routes in the state in one of the first drafts of the US routes system: 10, 20, 30, 40, 50 and 60.

[ethanhopkin14]

I know it's not intrastate, but it's worth nothing that US 59 is out of place in the grid, as it's entirely west of US 71. I think I saw in Fictional once to renumber it to US 73, which would make more sense as it's between 71 and 75 most of the way.

The only reason I mentioned US-57 and US-96 being intrastate is because it makes their "out of grid-ness" that much more bizarre.  At least US-66 in the west was kinda almost south of US-60, but when it got closer and closer to Chicago, well yeah.

Same with US-54.  It starts in Illinois and Missouri south of US-50 and north of US-60, but by the time it gets into New Mexico and Texas for the second time, it is way out of grid.  The intrastate ones are even more bizarre. 

But yes, US-59 is entirely out of grid.  I have never understood it's numbering.  Same with US-6.  It is never in grid, and in the west it is laughably out of grid. 

[US20IL64]

Some US highways were built diagonally. That's how they are, 

[NWI_Irish96]

Some US highways were built diagonally. That's how they are, 

I'm not in favor of wholesale changes now, but when they originally numbered these roads, they could have reserved 1xx numbers for diagonal routes and let "child" routes use 2xx and up.

[US 89]

I also found it odd that US-87 was in central Texas, yet the next odd number up, US-89 goes east of the Grand Canyon and goes through Utah.   

That whole bit of US 87 in Texas wasn't originally part of the route. For the first 10 years of its existence, the south end was in Rawlins and the whole route was much more grid-appropriate. Back then, US 89 did not extend north of Spanish Fork and US 91 actually ended at US 87 in Great Falls.

I sometimes wonder if, had all roads designated as US highways today existed back then, if US 87 would have been assigned to today's US 191 through Arizona/Utah/Wyoming. That would have put it about halfway between US 85 and US 89 for the majority of its route.

[SkyPesos]

I sometimes wonder if, had all roads designated as US highways today existed back then, if US 87 would have been assigned to today's US 191 through Arizona/Utah/Wyoming. That would have put it about halfway between US 85 and US 89 for the majority of its route.

That was one of my numbering experiments that I did a while ago in fictional. Since the population of the west is significantly larger than back in 1926 (wow can't believe the US routes system is almost 100 years old!), I pushed some numbers west, starting from around the 50s range for odd numbers. Like I placed 51 on current 61, 61 on current 59/71, 71 on current 83, 81 on current 85/87, and 91 on current 93/95. This omitted the need for 101 on the west coast, and spread the numbers out a bit more in the central US.

[Mapmikey]

I always found it odd that I-35 in Texas replaced US-81.  35 (and 45 being close to it) is a number that's closer to the middle of the grid, which Texas is close to the center, but 81 seems way too far to the west.  I found it odd that in Texas, the grid is already shifted to 81.  Yes, the country is more sparsely populated heading west from US-81, so the grid can get more spaced out in the graduations, but I always felt it was too far shifted.   

Yes the US Highway grid is was very very flawed, while the Interstate grid seemed to try to correct the errors made in the US grid, but the American southwest is one of the areas where the grid seemed to work, but the numbers seemed unnecessarily cramped (and by that I mean the north-south grid starts to run out of numbers even as far east as east Texas). 

I also found it odd that US-87 was in central Texas, yet the next odd number up, US-89 goes east of the Grand Canyon and goes through Utah.   

On another note, Texas is the proud owner of two horrible intrastate grid violators; US-57 and US-96.  Now, while US-57 is basically a continuation of Federal Route 57, US-96 is a mystery as to why it was numbered that way.  The only thing it has going for it is at one point it is south of US-90, but I for the life of me have no idea why it was numbered even although it's a north-south route.  This isn't a fact, since I did no research on it, but are there any other states that have 2 or more US routes that are this level horrible grid violators?  Intrastate would be preferable, but they don't have to be.   

US 87 didn't exist south of Wyoming until 1934.

US 96 is the product of a simple route swap with US 59.

The routing of US 59 being west of US 71 everywhere is a product of all the odd numbers already in use from 61-77.  I guess they could've gone with 79 but then it would be east of 75 and 77 its whole length.  There were also efforts to incorporate 73 into some of the southrn part of 59 but that didn't pan out.

[achilles765]

It seems to me like there is a kind of unofficial pattern to some of the routes based on the ending digit...
other than the usual x0 and x5 being major coast to coast/border-to-border routes

X1 routes seem to be long-is diagonal North-South routes that connect regions (future I-11, I-71, I-81, I-91)
x2 seem to be shorter east-west routes that connect one or two cities and are either intrastate or barely enter a second state (I-2, I-12 are both intrastate, I-22 is probably the one that is in another state the longest, future I-42, I-72 which barely enters Missouri, I-82)
Haven't noticed anything special about x3
x4 seem to be longish diagonal east-west routes that are almost like secondary major east west routes (I-4 being the only shorter one, but future I-14, I-24, I-44, I-64, I-74, both I-84s, I-94)
x6- shorter regional east-west routes that are intrastate or very nearly. (I-16, I-26, I-66, I-76, I-86, I-96)
x7- short north-south routes.  almost all are intrastate with the exception of I-57 and I-77. Usually connect two cities in a state, with one being a city that is not otherwise connected to any other major route (I-17 connecting Phoenix and Flagstaff, I-27 connecting Lubbock and Amarillo, I-37 connecting San Antonio and Corpus Christi, I-57, while longer basically connects Memphis and Chicago, I-77 is the exception, I-87, and I-97)
x8 are the most uncommonly used route numbers.  There are currently only four: I-8, I-68, I-78, and I-88.  These seem like short one or two state east-west routes but I notice no other noticeable traits.
x9 seem to be the secondary major north-south routes, with the exception of I-19 and I-99.. (I-19, I-29 from KC to Canada, I-39 doesn't fit totally, I-49, I-59, definitely I-69 once complete, I-79, I-89)

Just some things I noticed.  Now, I have expanded on this and begun to make a new grid system for 2dis based on this, which I may post in fictional once I complete it.

[dvferyance]

I-59 is 445 miles long yet it's northernmost miles are in Georgia still in the deep south.

[Hobart]

This is about a former US route but whatever.

So US-30A used to run along the route of Illinois 38. I heard the number of Illinois 38 was selected because it sounds like "30 - A".

[SkyPesos]

Highest difference between two same direction interstates intersecting

E-W: I-40 and I-74 (34)
N-S: I-35 and I-69(W) (34)

[ethanhopkin14]

Highest difference between two same direction interstates intersecting

E-W: I-40 and I-74 (34)
N-S: I-35 and I-69(W) (34)

Incorrect:

[US20IL64]

This is about a former US route but whatever.

So US-30A used to run along the route of Illinois 38. I heard the number of Illinois 38 was selected because it sounds like "30 - A".

Before 1971, route was known as ALT 30. The US shield numbered 30 and "ALT" above it. Going further back, was called US-330.

[Evan_Th]

OK, @ethanhopkin14, where is that photo showing, and what's it supposed to be?  I'm guessing US 90?

[TheHighwayMan3561]

OK, @ethanhopkin14, where is that photo showing, and what's it supposed to be?  I'm guessing US 90?

I assume Texas, given the pitchfork posts.

[ethanhopkin14]

OK, @ethanhopkin14, where is that photo showing, and what's it supposed to be?  I'm guessing US 90?

I assume Texas, given the pitchfork posts.

Correct, it's Texas and supposed to be U.S. 90. Also dead giveaway it's Texas, and that it's a rather older picture, by the night speed limit.