Looking at the current northern terminus of Interstate 49 in Kansas City, I get upset it terminates into I-435 (or I-470, I am not really sure where the signage stops). I would rather it continue on US-71 and terminate into downtown Kansas City so it can party with the rest of the routes. It got me thinking about how many times in the system do mainline interstates terminate into 3dis, giving them indirect access to another mainline interstate?
I-22 into I-269 south of Memphis?
I-88/IL eastern terminus in Hillside @ I-290 and I-294
One could make the argument that the route across Chicago's West Side to the Circle Interchange and Congress Pkwy Downtown should be numbered I-88 instead of I-290, but it is not
Eastern ends of I-64 and I-70.
Still at present: Original/Northern segment of I-69 at the southern terminus @ I-465 NE side in Indy. Once INDOT finishes the Martinsville-465 SW side segment, then I-69 can come off this list
I-97 at both ends (695, unsigned 595)
In Raleigh, NC, I-87 actually has a 3 mile overlap with I-440 so that it can properly end at I-40. Otherwise, it would just end at I-440 and require travel on I-440 to reach I-40. Once (if ever) it is built into Hampton Roads, it will likely terminate at the I-64 / I-464 interchange, though there's been speculation on this forum that it may replace I-464 and continue north into Downtown Norfolk, where it would terminate at I-264.
I-64 in Hampton Roads terminates at I-664 / I-264, though since I-64 is the only interstate in/out of the area, there's no using 3di to connect to another interstate, though technically following I-664 does loop you back to I-64 in Hampton, and significantly cuts off the distance using I-64 back around through Norfolk.
Eastern I-76 terminates at I-295. Many have argued that I-76 should continue on NJ 42 and the Atlantic City Expressway to the shore...
On a tangentially related note, I-390 is sort of like an extension of I-99.
Although I-99 technically ends at I-86, the fictional proposals to extend either I-99 or I-83 to Rochester (via a multiplex with I-86) are never-ending.
I-4's western terminus is at I-275 in Tampa.
At the moment, I-11's Northern Terminus is at I-215 and I-515. Not for too much longer, tho
The REAL I-87 terminates at I-278
And I-70 for all intents and purposes terminates at I-695
In the early 1980s, the plan was to have the eastern I-84 terminate at I-395 (RI cancelled their segment before CT did)
Why is this a problem? Some 2DIs don't even terminate at other Interstates, even ones that don't go to Canada's or Mexico's border crossings.
Quote from: stridentweasel on August 21, 2020, 02:28:33 PM
Why is this a problem? Some 2DIs don't even terminate at other Interstates, even ones that don't go to Canada's or Mexico's border crossings.
I-90 doesn't end at an interstate at either end. It ends at WA 519 at its western end and MA 1A at its eastern end.
I-45 and I-345.
Does it matter? An interstate's an interstate.
Quote from: Roadgeekteen on August 21, 2020, 10:18:58 PM
I-45 and I-345.
I-45 also terminates into I-30 at that junction, which connects to I-35E.
Quote from: stridentweasel on August 21, 2020, 02:28:33 PM
Why is this a problem? Some 2DIs don't even terminate at other Interstates, even ones that don't go to Canada's or Mexico's border crossings.
It doesn't "matter", it is just an observation since the original plan was to connect these mainline interstates in the downtowns of major cities. We have gotten a little away from that where we see main line interstates terminate into 3dis, indirectly connecting them to another 2di in the same metro area.
It is just like "that guy is tall and his friend is short" there isn't a problem, just an observation.
Technically, the eastern I-84 ends at I-380 near Scranton/Wilkes-Barre, although they both continue to their mutual end at I-81.
Quote from: ethanhopkin14 on August 24, 2020, 08:52:52 AM
Quote from: stridentweasel on August 21, 2020, 02:28:33 PM
Why is this a problem? Some 2DIs don't even terminate at other Interstates, even ones that don't go to Canada's or Mexico's border crossings.
It doesn't "matter", it is just an observation since the original plan was to connect these mainline interstates in the downtowns of major cities. We have gotten a little away from that where we see main line interstates terminate into 3dis, indirectly connecting them to another 2di in the same metro area.
It is just like "that guy is tall and his friend is short" there isn't a problem, just an observation.
Fair enough. To be brutally honest, there's a good reason why I-49 doesn't go to downtown Kansas City: the expressway and partial freeway shouldn't have even built in the first place, and the land should never have been taken from those neighborhoods. That alignment of US 71 is a relic of racist land acquisition and freeway building policies. Completing the middle portion as an expressway instead of a freeway was a problematic compromise, because it poses serious safety problems. However, it will be hard to fix it in a manner that honors the neighborhoods' needs, and it's often a subject on Fictional Highways and other boards here.
Actually, if you go back far enough, the original concept for Interstates was
not to have them go through city centers but rather have them go around them, in a similar fashion to the Pennsylvania Turnpike. But then Robert Moses, racism, and abuse of the Urban Renewal program happened.
As for the Kansas City example, I could think of
several re-numberings that would connect all the 2DIs together without pushing I-49 through the east side and to Downtown, but again, that's a topic for Fictional Highways, and some of the ideas have already been discussed there.
I-70 ends at I-695 for a similar good reason. I could think of one or two Fictional Highways re-numberings to connect the 2DIs around Baltimore, too. The thing is, re-numberings rarely happen IRL because of the potential to cause confusion, at least in the short term (although, some re-numberings could really have a long-term navigational benefit in terms of systematic "clean-up").
Why doesn't I-76 continue onto the Atlantic City Expressway instead of ending at I-295? That's a good question, and I think others have posted answers before.
I could think of a Fictional Highways re-numbering to connect I-22 to I-55, and that one's so new, it makes me wonder why they didn't number it that way in the first place, unless it's a case of "Worship the Mighty I-69!"
Quote from: stridentweasel on August 24, 2020, 10:30:23 AM
Quote from: ethanhopkin14 on August 24, 2020, 08:52:52 AM
Quote from: stridentweasel on August 21, 2020, 02:28:33 PM
Why is this a problem? Some 2DIs don't even terminate at other Interstates, even ones that don't go to Canada's or Mexico's border crossings.
It doesn't "matter", it is just an observation since the original plan was to connect these mainline interstates in the downtowns of major cities. We have gotten a little away from that where we see main line interstates terminate into 3dis, indirectly connecting them to another 2di in the same metro area.
It is just like "that guy is tall and his friend is short" there isn't a problem, just an observation.
Fair enough. To be brutally honest, there's a good reason why I-49 doesn't go to downtown Kansas City: the expressway and partial freeway shouldn't have even built in the first place, and the land should never have been taken from those neighborhoods. That alignment of US 71 is a relic of racist land acquisition and freeway building policies. Completing the middle portion as an expressway instead of a freeway was a problematic compromise, because it poses serious safety problems. However, it will be hard to fix it in a manner that honors the neighborhoods' needs, and it's often a subject on Fictional Highways and other boards here.
Actually, if you go back far enough, the original concept for Interstates was not to have them go through city centers but rather have them go around them, in a similar fashion to the Pennsylvania Turnpike. But then Robert Moses, racism, and abuse of the Urban Renewal program happened.
As for the Kansas City example, I could think of several re-numberings that would connect all the 2DIs together without pushing I-49 through the east side and to Downtown, but again, that's a topic for Fictional Highways, and some of the ideas have already been discussed there.
I-70 ends at I-695 for a similar good reason. I could think of one or two Fictional Highways re-numberings to connect the 2DIs around Baltimore, too. The thing is, re-numberings rarely happen IRL because of the potential to cause confusion, at least in the short term (although, some re-numberings could really have a long-term navigational benefit in terms of systematic "clean-up").
Why doesn't I-76 continue onto the Atlantic City Expressway instead of ending at I-295? That's a good question, and I think others have posted answers before.
I could think of a Fictional Highways re-numbering to connect I-22 to I-55, and that one's so new, it makes me wonder why they didn't number it that way in the first place, unless it's a case of "Worship the Mighty I-69!"
I am not a fan of renumbering highways unless they were spurs before and became a part of the new longer 2di, so my intention of this thread wasn't to renumber anything, just more of what other 2dis am I not aware of that terminate into 3dis?
Quote from: Henry on August 24, 2020, 10:11:05 AM
Technically, the eastern I-84 ends at I-380 near Scranton/Wilkes-Barre, although they both continue to their mutual end at I-81.
It's more like I-380 ends at I-84, since mileposts only show I-84 distances and not I-380.
Quote from: stridentweasel on August 24, 2020, 10:30:23 AM
I could think of a Fictional Highways re-numbering to connect I-22 to I-55, and that one's so new, it makes me wonder why they didn't number it that way in the first place, unless it's a case of "Worship the Mighty I-69!"
In this case, planning and official designation of I-269 came before I-22. We knew it was going to be I-269 two decades before I-22 came about.
Quote from: froggie on August 24, 2020, 11:50:27 AM
Quote from: stridentweasel on August 24, 2020, 10:30:23 AM
I could think of a Fictional Highways re-numbering to connect I-22 to I-55, and that one's so new, it makes me wonder why they didn't number it that way in the first place, unless it's a case of "Worship the Mighty I-69!"
In this case, planning and official designation of I-269 came before I-22. We knew it was going to be I-269 two decades before I-22 came about.
Well, actually they're about as old as each other, as I think my first correspondence about renumbering US 78 to I-22 with Senator Shelby's office was written about 1997 or 1998. Although I-69 was legislated in 1998, indeed I-22 wasn't legislated into existence in 2004. :(
.
I think most of us expected Tennessee to be willing to upgrade US 72 at least to I-240. If 22 ended there, it still would be ending at a 3di though! I think part of the "Bridges of Memphis" solution should be to route I-22 along I-269 and I-69 towards Tunica, and build a new bridge and connector route sweeping across the river and northward to end at I-40. Then traffic coming from I-30 & I-40 points west could completely bypass Memphis to the south on such an extended I-22... Then building a new I-55 bridge a thousand feet south of the current bridge could proceed without making Memphis a permanent traffic jam.
Since the whole idea of deploying additional freeways in dense urban areas is now both politically infeasible as well as virtually impossible from an economic standpoint, it would be expected that unless new Interstate corridors utilized existing facilities that weren't expected to be removed or the subject of efforts to do so, there would be more instances of these more rural corridors terminating at beltways than following the original "yellow book" plan into city centers; with the upshot that more 3di's will likely be pressed into service as 2di terminus points if and when new intercity/interregional Interstate corridors are planned and deployed.
Quote from: sturmde on August 24, 2020, 12:23:03 PM
Quote from: froggie on August 24, 2020, 11:50:27 AM
Quote from: stridentweasel on August 24, 2020, 10:30:23 AM
I could think of a Fictional Highways re-numbering to connect I-22 to I-55, and that one's so new, it makes me wonder why they didn't number it that way in the first place, unless it's a case of "Worship the Mighty I-69!"
In this case, planning and official designation of I-269 came before I-22. We knew it was going to be I-269 two decades before I-22 came about.
Well, actually they're about as old as each other, as I think my first correspondence about renumbering US 78 to I-22 with Senator Shelby's office was written about 1997 or 1998. Although I-69 was legislated in 1998, indeed I-22 wasn't legislated into existence in 2004. :(
.
I think most of us expected Tennessee to be willing to upgrade US 72 at least to I-240. If 22 ended there, it still would be ending at a 3di though! I think part of the "Bridges of Memphis" solution should be to route I-22 along I-269 and I-69 towards Tunica, and build a new bridge and connector route sweeping across the river and northward to end at I-40. Then traffic coming from I-30 & I-40 points west could completely bypass Memphis to the south on such an extended I-22... Then building a new I-55 bridge a thousand feet south of the current bridge could proceed without making Memphis a permanent traffic jam.
Up until his political demise circa 2001-02, Sen. Trent Lott (R-MS) was the "designated ball-carrier" for the I-22-over-US-78 concept. However, there was no love lost (although both were Republicans) between Lott and then-Senator Bill Frist (R-TN); Frist saw no reason to champion a I-22 incursion into TN along Lamar Ave, considering that corridor to have limited benefit for his own state (besides simply wanting to stick it to Lott!). Matters were at an impasse up to Lott's scandal, and as of the end of 2001 the project was on hold. But enough Alabama-based interests were able to intervene and get Sen. Shelby involved by early 2003; he essentially assumed Lott's previous "spearheading" role and was able to get both an amended corridor definition (HPC #45) with the I-22 designation attached into the 2004 USDOT authorizing legislation. So as of March '04 the project was "back in business", so to speak -- although it took another 13 years to achieve completion -- and that only because of the I-269 construction "dovetailing" into the upgrading of the older/original US 78 freeway across northern MS. To this day, there has been no revival of interest in extending I-22 into TN; its western terminus at I-269 is, at least in official circles, considered adequate. Also, there is little to speak of in the way of trailblazer signage for I-22 at the various I-269 interchanges in either MS or TN; it seems to be the proverbial "red-headed stepchild" of the region.
I'm pretty sure that I-80 was intended to terminate at I-280 in San Francisco and did effectively terminate at I-480/SR 480 for a while.
Quote from: ari-s-drives on August 26, 2020, 03:37:13 PM
I'm pretty sure that I-80 was intended to terminate at I-280 in San Francisco and did effectively terminate at I-480/SR 480 for a while.
Well, I think it ended at US 101...
Quote from: Hwy 61 Revisited on August 26, 2020, 04:26:28 PM
Quote from: ari-s-drives on August 26, 2020, 03:37:13 PM
I'm pretty sure that I-80 was intended to terminate at I-280 in San Francisco and did effectively terminate at I-480/SR 480 for a while.
Well, I think it ended at US 101...
That's been a questionable issue for some time. Technically CASR 80 extends to US 101, but the chargeable portion of I-80 ended either at (a) the former I/CA-480 interchange or (b) the 5th Street left exit (the original end of the Bay Bridge before the Skyway was cut in in the early '50's) after the Central Freeway's Interstate status was, along with the I-480 stub, rescinded circa 1965. Nevertheless, the section between either of the two cited endpoints and the US 101 interchange has always been signed, via both trailblazer and reassurance shields, as I-80. It's one of those "if it looks like a duck" scenarios. Since the original I-480 interchange at the west end of the Bay Bridge/I-80 was also supposed to be the access to southward I-280 after that route's realignment over former CA 82 and CA 87 back in '65, it would have functioned as a mutual
official terminus for both Interstates, although the section west from there likely would have been, like today, CASR-80 signed as I-80; it's unlikely that green CA 80 spades would have been deployed -- although "TO" banners may well have topped the I-80 shields in that section (with "TO" US 101 in the other).
Quote from: sparker on August 26, 2020, 05:36:25 PM
Quote from: Hwy 61 Revisited on August 26, 2020, 04:26:28 PM
Quote from: ari-s-drives on August 26, 2020, 03:37:13 PM
I'm pretty sure that I-80 was intended to terminate at I-280 in San Francisco and did effectively terminate at I-480/SR 480 for a while.
Well, I think it ended at US 101...
That's been a questionable issue for some time. Technically CASR 80 extends to US 101, but the chargeable portion of I-80 ended either at (a) the former I/CA-480 interchange or (b) the 5th Street left exit (the original end of the Bay Bridge before the Skyway was cut in in the early '50's) after the Central Freeway's Interstate status was, along with the I-480 stub, rescinded circa 1965. Nevertheless, the section between either of the two cited endpoints and the US 101 interchange has always been signed, via both trailblazer and reassurance shields, as I-80. It's one of those "if it looks like a duck" scenarios. Since the original I-480 interchange at the west end of the Bay Bridge/I-80 was also supposed to be the access to southward I-280 after that route's realignment over former CA 82 and CA 87 back in '65, it would have functioned as a mutual official terminus for both Interstates, although the section west from there likely would have been, like today, CASR-80 signed as I-80; it's unlikely that green CA 80 spades would have been deployed -- although "TO" banners may well have topped the I-80 shields in that section (with "TO" US 101 in the other).
Interstate 345 approves of this message.
Quote from: ethanhopkin14 on August 26, 2020, 05:50:35 PM
Quote from: sparker on August 26, 2020, 05:36:25 PM
Quote from: Hwy 61 Revisited on August 26, 2020, 04:26:28 PM
Quote from: ari-s-drives on August 26, 2020, 03:37:13 PM
I'm pretty sure that I-80 was intended to terminate at I-280 in San Francisco and did effectively terminate at I-480/SR 480 for a while.
Well, I think it ended at US 101...
That's been a questionable issue for some time. Technically CASR 80 extends to US 101, but the chargeable portion of I-80 ended either at (a) the former I/CA-480 interchange or (b) the 5th Street left exit (the original end of the Bay Bridge before the Skyway was cut in in the early '50's) after the Central Freeway's Interstate status was, along with the I-480 stub, rescinded circa 1965. Nevertheless, the section between either of the two cited endpoints and the US 101 interchange has always been signed, via both trailblazer and reassurance shields, as I-80. It's one of those "if it looks like a duck" scenarios. Since the original I-480 interchange at the west end of the Bay Bridge/I-80 was also supposed to be the access to southward I-280 after that route's realignment over former CA 82 and CA 87 back in '65, it would have functioned as a mutual official terminus for both Interstates, although the section west from there likely would have been, like today, CASR-80 signed as I-80; it's unlikely that green CA 80 spades would have been deployed -- although "TO" banners may well have topped the I-80 shields in that section (with "TO" US 101 in the other).
Interstate 345 approves of this message.
I-345 vs. the questionable I-80 "stub" is pretty much apples vs. oranges. The former is actually an Interstate route -- albeit unsigned -- that functions as an extension of I-45 north of that route's terminus at I-30; it's on the FHWA's Interstate "log sheet". IIRC, I-80's defined western terminus is the west end of the Bay Bridge, which makes the Skyway from there to US 101 simply a state-owned freeway; it's
not on that same log. But I-345 is interesting in that it exists at all; why TxDOT didn't simply apply for that section of freeway to be the northernmost section of I-45 (and either sign it or not) is, at least to me, a mystery. The only other instance I can think of that such a configuration occurred or was planned was the I-79/I-179 continuum at Erie, PA; originally, the "stub" of the I-79 facility located north of I-90 and south of Erie was to be designated as I-179, but that concept only lasted for a couple of years until someone thought it was just plain silly and arranged to have it redesignated as the continuation of I-79. Now -- whether that would have had any bearing on the folks pressing for I-345's teardown is simply conjecture at this point.
Had an idea -- one that would make the aforementioned Dallas "teardown" parties gnash their teeth -- TxDOT pursues I-45 up US 75 to the state line, subsuming I-345 in the process. Then they could ask that the Woodall/TX 366 freeway be the
new I-345 as an access route from I-35E to the new northern section of I-45. Would like to be the proverbial "fly on the wall" if and when that would occur!
Quote from: sparker on August 26, 2020, 06:47:07 PM
Quote from: ethanhopkin14 on August 26, 2020, 05:50:35 PM
Quote from: sparker on August 26, 2020, 05:36:25 PM
Quote from: Hwy 61 Revisited on August 26, 2020, 04:26:28 PM
Quote from: ari-s-drives on August 26, 2020, 03:37:13 PM
I'm pretty sure that I-80 was intended to terminate at I-280 in San Francisco and did effectively terminate at I-480/SR 480 for a while.
Well, I think it ended at US 101...
That's been a questionable issue for some time. Technically CASR 80 extends to US 101, but the chargeable portion of I-80 ended either at (a) the former I/CA-480 interchange or (b) the 5th Street left exit (the original end of the Bay Bridge before the Skyway was cut in in the early '50's) after the Central Freeway's Interstate status was, along with the I-480 stub, rescinded circa 1965. Nevertheless, the section between either of the two cited endpoints and the US 101 interchange has always been signed, via both trailblazer and reassurance shields, as I-80. It's one of those "if it looks like a duck" scenarios. Since the original I-480 interchange at the west end of the Bay Bridge/I-80 was also supposed to be the access to southward I-280 after that route's realignment over former CA 82 and CA 87 back in '65, it would have functioned as a mutual official terminus for both Interstates, although the section west from there likely would have been, like today, CASR-80 signed as I-80; it's unlikely that green CA 80 spades would have been deployed -- although "TO" banners may well have topped the I-80 shields in that section (with "TO" US 101 in the other).
Interstate 345 approves of this message.
I-345 vs. the questionable I-80 "stub" is pretty much apples vs. oranges. The former is actually an Interstate route -- albeit unsigned -- that functions as an extension of I-45 north of that route's terminus at I-30; it's on the FHWA's Interstate "log sheet". IIRC, I-80's defined western terminus is the west end of the Bay Bridge, which makes the Skyway from there to US 101 simply a state-owned freeway; it's not on that same log. But I-345 is interesting in that it exists at all; why TxDOT didn't simply apply for that section of freeway to be the northernmost section of I-45 (and either sign it or not) is, at least to me, a mystery. The only other instance I can think of that such a configuration occurred or was planned was the I-79/I-179 continuum at Erie, PA; originally, the "stub" of the I-79 facility located north of I-90 and south of Erie was to be designated as I-179, but that concept only lasted for a couple of years until someone thought it was just plain silly and arranged to have it redesignated as the continuation of I-79. Now -- whether that would have had any bearing on the folks pressing for I-345's teardown is simply conjecture at this point.
Had an idea -- one that would make the aforementioned Dallas "teardown" parties gnash their teeth -- TxDOT pursues I-45 up US 75 to the state line, subsuming I-345 in the process. Then they could ask that the Woodall/TX 366 freeway be the new I-345 as an access route from I-35E to the new northern section of I-45. Would like to be the proverbial "fly on the wall" if and when that would occur!
It was a joke referring to I-345 signed as SOUTH I-45 (congruent to US-101) southbound and NORTH US-75 (congruent to I-80) northbound. Just in both scenarios, they are completely different numbered highways then the two highways they connect via one stretch of pavement, acting secretly as an extension of both highways depending on which way you are traveling.
Quote from: ethanhopkin14 on August 26, 2020, 08:00:14 PM
Quote from: sparker on August 26, 2020, 06:47:07 PM
Quote from: ethanhopkin14 on August 26, 2020, 05:50:35 PM
Quote from: sparker on August 26, 2020, 05:36:25 PM
Quote from: Hwy 61 Revisited on August 26, 2020, 04:26:28 PM
Quote from: ari-s-drives on August 26, 2020, 03:37:13 PM
I'm pretty sure that I-80 was intended to terminate at I-280 in San Francisco and did effectively terminate at I-480/SR 480 for a while.
Well, I think it ended at US 101...
That's been a questionable issue for some time. Technically CASR 80 extends to US 101, but the chargeable portion of I-80 ended either at (a) the former I/CA-480 interchange or (b) the 5th Street left exit (the original end of the Bay Bridge before the Skyway was cut in in the early '50's) after the Central Freeway's Interstate status was, along with the I-480 stub, rescinded circa 1965. Nevertheless, the section between either of the two cited endpoints and the US 101 interchange has always been signed, via both trailblazer and reassurance shields, as I-80. It's one of those "if it looks like a duck" scenarios. Since the original I-480 interchange at the west end of the Bay Bridge/I-80 was also supposed to be the access to southward I-280 after that route's realignment over former CA 82 and CA 87 back in '65, it would have functioned as a mutual official terminus for both Interstates, although the section west from there likely would have been, like today, CASR-80 signed as I-80; it's unlikely that green CA 80 spades would have been deployed -- although "TO" banners may well have topped the I-80 shields in that section (with "TO" US 101 in the other).
Interstate 345 approves of this message.
I-345 vs. the questionable I-80 "stub" is pretty much apples vs. oranges. The former is actually an Interstate route -- albeit unsigned -- that functions as an extension of I-45 north of that route's terminus at I-30; it's on the FHWA's Interstate "log sheet". IIRC, I-80's defined western terminus is the west end of the Bay Bridge, which makes the Skyway from there to US 101 simply a state-owned freeway; it's not on that same log. But I-345 is interesting in that it exists at all; why TxDOT didn't simply apply for that section of freeway to be the northernmost section of I-45 (and either sign it or not) is, at least to me, a mystery. The only other instance I can think of that such a configuration occurred or was planned was the I-79/I-179 continuum at Erie, PA; originally, the "stub" of the I-79 facility located north of I-90 and south of Erie was to be designated as I-179, but that concept only lasted for a couple of years until someone thought it was just plain silly and arranged to have it redesignated as the continuation of I-79. Now -- whether that would have had any bearing on the folks pressing for I-345's teardown is simply conjecture at this point.
Had an idea -- one that would make the aforementioned Dallas "teardown" parties gnash their teeth -- TxDOT pursues I-45 up US 75 to the state line, subsuming I-345 in the process. Then they could ask that the Woodall/TX 366 freeway be the new I-345 as an access route from I-35E to the new northern section of I-45. Would like to be the proverbial "fly on the wall" if and when that would occur!
It was a joke referring to I-345 signed as SOUTH I-45 (congruent to US-101) southbound and NORTH US-75 (congruent to I-80) northbound. Just in both scenarios, they are completely different numbered highways then the two highways they connect via one stretch of pavement, acting secretly as an extension of both highways depending on which way you are traveling.
You know, I did not know that! I've been on I-30 countless times through central Dallas, but never had the need to use I-345, so its signage characteristics remained unknown -- although I knew it was unsigned
as I-345. Of course the scheme described above makes sense -- the whole thing is simply a "bridge" between US 75 and I-45.