jpne: Japan Expressways

[si404]

Should all u-turn-only exits be included?

I would like to add them, though there's no should about doing so.

Is N# how national highways should be referenced?

It's how I have referenced them - it seemed logical with the E for Expressways. Have you another suggestion?

Did you use E1A, E1 and E20 as names because their numbers (1, 4-1, 6) did not match the normal exit number sequence?

Yes. Thoughts from the floor on this.

Alternatively I could call them 1(E1A), 4-1(E1) and 6(E20) - as numbered exits from another route's exit numbering system, but that strikes me as rather pointless.

[si404]

I apologize for being unclear about why I asked this question.  I don't know the future plans for Japan - divided or undivided.  If Japan is an undivided country I don't need to worry about  prefectural boundaries.

I found it clear. No plans to split Japan at this time. We'll cross that bridge if we come to it.

[nezinscot]

Thanks for the clarifications.

I decided to work my way north - Kyushu to Hokkaido.  I thought things would be simpler down south. They aren't.  Here are a few updates for some of the shorter Kyushu expressways.

E77Kum
a) has new exits IC2 and IC3

E77Tak - new road
a) There is an additional section of E77 open. It is a tunnel between N218 in Takachiho and a farm road that leads to N218. I suggest using Tak(achino) as the name -  it's a popular tourist site.

E96
a) E96 branches just before exit 11-3. Branch A goes to P113. Branch B goes to P235 and is part of the current entry for E96.  A new entry for Branch A is needed.
b) I would use E34 instead of 11 as the first exit name.  11 is the exit number on E34 for getting on E96.

E97
a) You might be able to use the IC numbers instead of route numbers:  N10(1), ToN213(Jct2), P4(3).  E97 is made up of three pre-existing roads. I don't know if the numbers being sequential is a fortuitous accident, or not.
b) Exit IC4 does not have a waypoint. It goes to P404.

E98
a) E98 starts at IC5, not IC4-1. The highway between IC4-1 and IC5 appears to be a branch of E10.  It is definitely a part of the Miyazaki Expressway.  I used GSV to look for E10/E98 signage, but didn't find any in the 2017-18 street views.  The Japanese wikipedia page for the Miyazaki IC (5) says that it is on E10 and that E98 is a connecting road.
b) We probably need a new entry for the E10? branch between IC4-1 and IC5.

[nezinscot]

More Kyushu.

E3AYat
a) The existing exit numbers should be 1 thru 5 (1-1 became 2).
b) The road has been extended and now ends at IC6.

E3AIzu
a) The road now starts at IC9.

E3
a) There are four new ICs to add:  4-2, 14-1, 19-1, and 25-2.

[nezinscot]

The rest of Kyushu, plus Okinawa

E10
a) Exits 10(Hig) thru 13(Hig) are actually numbered 9-1 thru 9-4 (verified with GSV). Because of this there is probably no need to use the (Hig) and (Oita) indicators in the exit names.
b) Need to add exits 10-1, 24-1, 28-1.
c) Need to add exit 3-1(Miy).

E34
a) Consider using E10 as the exit name instead of 10(Oita)
b) Add new exit 9-1(Oita)
c) Add new exits 3-1(Nag) and 9-1(Nag)
d) The 1(Nag) exit was confusing when I looked at it on GSV. I can see why you used 1 and 1a. You could alternatively use N3 and N34 which is what the signs on E34 use.

E35
b) The exits are listed low to high. Should they be flipped? The E35 Japanese wikipedia page lists exits starting in Fukuoka and ending at E34. E35Fuk, E35Mat, and E35Kar use the order wikipedia uses.

E35Fuk
a) Consider using FEC as the exit name instead of Fuk
b) The road ends at P573, not P12.  Move the P12 point to P573 and rename it.  Or name it N202 because that is the continuing road.
c) The other exits all connect to N202 which follows underneath the expressway, but the town names are less confusing that using N202A thru N202D, plus they mirror the exit signs on the expressway.  I would also use Ima(juku) instead of P561; P561 is not listed on the exit sign.

E35Kar
a) Consider using the IC numbers (24 thru 18) instead of road names.

E35Mat
a) Consider using the IC numbers (14 thru 11) instead of road names.

E58 (Okinawa)
a) Need to add exit 3-1
b) At exit 1-1, there is a long exit west to P82. I could not find any indication on the web that this long exit is considered a separate branch of E58, so what exists now is probably OK.

E78
a) Consider using E3 as the exit name instead of 25-1 which is the E3 exit number for E78

E78Miy
a) Consider using E10 as the exit name instead of 4-1 which is the E10 exit number for E78Miy

[nezinscot]

Hokkaido expressways

E5
a) The exit numbering is now sequential S to N, from 6 to 48.  20(S) is 6, 13(N) is 48, 1 is 32.
b) Need to add exit 21 - between 7(S) and 6(S)
c) Need to add exit 27 - between 4(S) and 3(S)
d) Need to add exit 31 - between 2(S) and 1
e) Need to add exit 33 - 0.5 km east of the E5, E5A junction. The exit is almost part of the junction. Coming from the north on E5, exit 33 goes straight to N274, while bearing left is exit 32 which continues E5.  Only the latest GSV shows the new exit numbers.
f) Need to add exit 40 - between 7(N) and 8(N)

E5Toy
a) The Japanese wikipedia page for the road says that as of 2020 the exit numbers are no longer used. OpenStreetMaps uses IC names without numbers. But GSV from 2018 shows all four exit numbers in use. If you decide to follow OSM and wikipedia, these names could be used for the exits
1: P121
2: P84
3: P923
4: N40

E5A
a) Use E5 instead of 1-1.
b) Exit 4 is missing. The waypoint for exit 3 is located between 3 and 4. Add 4 and move 3 east of P231.  3 (exit westbound) and 4 (exit eastbound) are a pair, but they are numbered separately.
c) The waypoints for 1 and 2 are not positioned at the exits. 2 is too far NW and 1 is too far SE. (Exits 1 and 2 are similar to 3 and 4.)

E5AKur
a) The Japanese wikipedia page for the road says that as of 2020 the exit numbers are no longer used. OpenStreetMaps uses IC names without numbers. GSV from 2018 shows the exit numbers in use.  If you decide to follow OSM and wikipedia, these names could be used for the exits
1: P344
2: N5

E38Kus
1) The road ends at exit 20, which could be named E44 because E44 begins at that point.

E44
a) This road needs to be added. It begins at exit 20 at the end of E38Kus. It has two exits - E38 (20) and 21.

E44Nem (for Nemuro, at the eastern tip of Hokkaido)
a) This road needs to be added. It has two exits - N44_S and N44_N.

E59
a) Exit 1 could be called E5.

[nezinscot]

Shikoku - Honshu connector expressways

E2Kim - new route
a) E28 does not extend to E2. A short branch of E2 heads south to connect to E28.
b) There are two waypoints - E2 (IC2 on E2) and E28 (IC1)
c) Kim is from the road name - Kimi Branch Line

E28
a) E28 does not extend to E2. It starts at IC1, which could be named E2Kim
b) New exit 7-1 needs to be added.
c) New exit 4-1 is part of the exit 4 complex at the Awaji Highway Oasis. 4-1 allows entry from P157 to the service area. Its location is WNW of the electric vehicle charging station at the north end of the Oasis parking lot.

E2Kur - new route
a) E30 does not extend to E2. A short branch of E2 heads south to connect to E30.
b) There are two waypoints - E2 (IC16 on E2) and E30 (IC1)
c) Kur is from the road name - Kurashiki Hayashima branch line

E30
a) E30 does not extend to E2. It starts at IC1, which could be named E2Kur
b) Exits 3-1, 3-2, and 3-3 only allow entry to local residents and delivery vehicles (and the GSV vehicle). The toll booths at the exits require a separate payment card for islanders only.

[si404]

E2Kim - new route
a) E28 does not extend to E2. A short branch of E2 heads south to connect to E28.
b) There are two waypoints - E2 (IC2 on E2) and E28 (IC1)
c) Kim is from the road name - Kimi Branch Line

very clearly signed as E28 For Akashi Bridge at E2. Might be able to justify it being an E2 spur, counting that as a 'to' rather than the E2 signage at the other end, but that name doesn't appear at either end.

Same goes for all these spurs. It's a bit like Italy, but without the big chainage/confirmatory markers that justify the silly spurs that would more logically be the mainline of another route of the same system being included as signed.

I've done pretty much everything else, but I've not done the un-/not-really signed spurs. I might do them, but at the moment, I'm undecided.

[nezinscot]

I think the spurs are a result of the E highways largely being formed by combining pre-existing toll roads. The spurs and the main line are separate toll roads.  If you think the spurs are unnecessary, I don't disagree.  No one would be taking them unless they were using the other highway.

The 2016 government document defining the E roads only lists the pre-existing roads that will make up the highways. Start and end points are not listed, but I can usually figure them out from looking at the individual toll roads. It gets complicated because one toll road may be part of multiple E roads, or only partially part of one.

I've finally figured out that the "most likely correct" info on the E routes is to check the Japanese wikipedia pages for the individual junctions.  Each has a section called 隣 "Next to" which lists the roads leading into and out of the junction.  The constituent toll roads of the E highways have detailed wikipedia pages, including all the junctions and interchanges. (The english equivalent pages are almost always out-of-date.)  I'll look at the junctions for E28 and E30 again and see if I can find out more.

[nezinscot]

Japan's longest expressway

E4
a) Add exits 7-1, 10-1, 11-1, 15-1, 17-1, 31-1, 35-1, 40-1, and 42-1.
b) Waypoint 1 could be called S1/C3 or C3/S1.  S1 is the continuing road.
c) Waypoint 2 should be moved further south, to where the ramp toll-booths are. This is just NW of the southern IC2 label on OSM.

[nezinscot]

Northern Honshu

E4A
a) Add exit 5-2
b) On other roads you used X and Xa as waypoint names for complex junctions like 5-1.  I do think E45 is more descriptive than 5-1a.

E4AMic
a) Its correct.  I spent way more time on this one than I expected.  Looking at it on GSV had me skeptical - it isn't an expressway and looks more like a NH state highway through the White Mountains.  After some searching I did find multiple references to it being part of E4A.

E7
a) Waypoint E8/E42 should be E8/E49.

E7Oda
a) Waypoints 17 and 18 should be 26 and 27.

E13Inn (for Innai)
a) This is a new segment of E13, between E13Mas and E13,
b) Waypoints N13_S and N13_N

E13Mas
a) N13_Yaz, N13_Kam could be N13_N, N13_S

E45
a) Combine E45 and E45Ota. The connecting roadway opened in March.
b) Add exits 26, 27, and 28.  You might need 28 and 28a because the two sections of the exit are separated by a tunnel.
c) Move waypoint 25 to the exit. It is at the former end point.
d) Delete waypoint N45_KM.
e) N45_N could be just N45.
f) Waypoint 2 could be E6.

E45Hac
a) Consider using the exit number - 65 - instead of N45/N395_S

E46
a) Add exit 3-1(Aki)
b) Waypoint 1-1(Aki) is an exit to a rest area. It probably should be removed.
c) Waypoint 5-1(Aki) could be named E7
d) The Toki waypoints could be named 37(E4), 37-1(E4), and 38(E4)

E64Aji
a) Waypoint ToN101 should be moved east to the intersection with N101. The waypoints could then be N101_W, P31, N101_E

[nezinscot]

I rechecked E28 and E30.

It looks like E30 does connect to an E2 stub
Hayashima IC 隣 (next to)
    E2 - Sanyo Expressway Kurashiki Hayashima Branch Line
        (16) Kurashiki JCT - (1) Hayashima IC/TB
    E30 - Seto Chuo Expressway
        (1) Hayashima IC/TB - Tsubue PA - (2) Mizushima IC

Also, the description for the Kurashiki exit of the Sanyo Expressway says that it connects to the Sanyo Kurashiki branch and that it goes "in the direction of" E30.


But the data is conflicting on whether E28 connects directly to E2 with no stub, though I suspect the Kobe-Nishi IC info is wrong.
Kobe-Nishi IC 隣 (next to)
    E28 - Sanyo Expressway Kimi Branch Line
        (2) Miki JCT - (1) Kobe-Nishi IC
    E28 - Kobe Awaji Naruto Expressway
        (1) Kobe-Nishi IC/TB - (2) Fusehata JCT/IC

The Miki JCT next to info however, says that the exit goes onto an E2 stub.
    E2 Sanyo Expressway Main Line
        (1) Kobe-Kita IC - (2) Miki JCT - (3) Miki-Higashi IC
    E2 Sanyo Expressway Kimi Branch Line
        (2) Miki JCT - (1) Kobe-Nishi IC

Also, the description for the Kimi exit of the Sanyo Expressway says that it connects to the Sanyo Kimi branch and that it goes "in the direction of" E28.


Google Maps and OSM show the E2 stubs.   I think they do exist.  I'd be glad to volunteer to field check.

A sign like this https://www.google.com/maps/@34.8076878,135.071515,3a,30.2y,34.42h,99.82t/data=!3m7!1e1!3m5!1sUmfO1VHC5q_8YTwAfb2KyQ!2e0!5s20191201T000000!7i16384!8i8192 also shows E1A and E2A, which are not reached for many kilometers. I think the E28 here could be similar - its a "to" reference.

[si404]

I think the E28 here could be similar - its a "to" reference.

But so could the E2 signage at the other end.

The bar is a little higher when it comes to spurs - it needs something on the road saying it that without a doubt is actually a spur.

I've found this E2 confirmatory sign heading away from the E2 towards the E30. That is enough evidence for that. I'll have a look at the E28 one and see is there's similar.

[nezinscot]

I'm glad you found that confirmation marker.  It gives me more confidence about OSM and Google Maps show for expressways.

I just GSV traveled both directions on the E2-E28 connector and did not see any signs saying E2 or E28. The expressway numbering plan was announced in 2016. GSV was mostly from 2017-18 which might be too soon after the announcement for signs to be present.  You have better GSV foo than me, so you might find something if you look.

The GSV road name overlay did switch over from E2 to E28 at km 9.3 just N of the toll booth, which proves only that Google thinks there is a spur.  At that location northbound, there was a sign saying "From here, Sanyo Expressway" which is the E2 on its main line.  Again, not conclusive.

Another inconclusive data point:  The 2016 expressway numbering plan lists only the Kobe Awaji Naruto Expressway as part of E28. That expressway ends at the Kobe-Nishi IC.

[nezinscot]

The other Honshu-Shikoku connector is E76.  It seems to connect directly to E2 at IC22. 

Anecdotal evidence:
E2 does not list a branch line for this IC.
The toll booth is just after the exit, not KMs further south like on E28 and E30.
The 2016 numbering document lists three roads as making up E76 - the northernmost one is N2.
The IC22 wikipedia page says that it connects to E76 and N2.

I have no suggested changes for either E76 or E76Sai.

I will be in Tennessee for the next two weeks and likely won't be able to review more roads till I return.