Worldbuilding Realism Consultation Thread Mk. 4

[The Soodean Imperium]

That's what I'd suspected. But here's my problem:

VERY WIP

The main shipping areas are in the northeast of Donggyŏng proper (north bank city), and in the east of Gyŏngpo (south bank city). The most active intercity line (both people and freight) would be the one to the southwest, with the one directly due north at a distant second. I can get Donggyŏng port freight to go north along the coastal line, which only passes through a few large towns, and get Gyŏngpo port freight to follow the south peninsula line, which eventually loops around to head southwest, but I can't find an easy way to send Donggyŏng port freight southwest without running the long way through a ~15-million-person city.

This is what led me to consider dedicated freight lines through the city center, which would at least allow me to bypass the busy stations and avoid passenger traffic. These could either be directly adjacent to the existing passenger lines or following a separate course with wider and fewer tunnels. The terrain west of Donggyŏng and south of Gyŏngpo is mildly mountainous (think Beijing not Denver) which makes a loop around the outskirts difficult but not impossible, and I would be willing to follow that path if it's deemed more feasible.

Timeline-wise, the original railway from Donggyŏng port inland would have been built in the 1870s or thereabouts, when the city limits were much smaller and passenger travel was lighter. Though I guess that can't stop me from re-routing rail freight onto new lines in the 1990s, when economic growth brings massive increases in both urban area and trade volume.

Usually there'd be at least one rail corridor for intercity passenger rail services so they wouldn't need to use smaller commuter rail networks. In that case the city would likely have two branch lines that connect to the main rail corridor. Industrial areas would largely be devoid of any commuter or passenger rail anyway. Or, transfer the cargo using trucks.

Does this mean I can safely run freight trains through the city as long as they use the intercity rail corridors? I'm still OK with making outer freight lines that bypass the city and its mountains but running them directly would shave maybe 100km off the distance.

As is, the rail lines marked on the map would be intercity corridors, or at least regional rail lines. I haven't even added commuter rail within the metropolitan area, which I might put on a smaller gauge and merge into the metro system. Really though I think I need to read up on the different categories of commuter rail, how they work in different countries... an S-Bahn style system might be nice.

[The Akasha Colony]

Does this mean I can safely run freight trains through the city as long as they use the intercity rail corridors? I'm still OK with making outer freight lines that bypass the city and its mountains but running them directly would shave maybe 100km off the distance.

It is possible. Amtrak runs a lot of its intercity services on freight lines, but this basically the reverse of what you were inquiring about, as Amtrak shares lines with freight trains rather than vice versa. It's not really a desirable system though and only exists because Amtrak does not have the funding or political support to build out its own dedicated rail network and freight operators are the only intercity rail services who own a sufficiently large track network. Amtrak has plenty of issues due to this system (and indeed, a lot of its issues can be traced directly back to this shared use model).

Ultimately I think it depends on the expected freight volume and use. Despite its own mountainous terrain, Japan has been willing to build out dedicated freight lines for its most heavily-trafficked routes (e.g. Tokaido freight line), independent of both the regular regional lines and the high-speed intercity lines, and this line runs straight to the Tokyo docks. If demand is sufficient for there to be a dedicated freight line, then one would probably be built. If there is not, then the trains will just be stuck running some indirect and possibly inconvenient routes but it's not a big enough issue to be relevant. In the US it's the reverse because outside of a few new state-sponsored rail programs, Amtrak doesn't have the volume, revenue, or political support to build its own network so it has to rely on a patchwork of freight and state-owned rail lines for its services.

In general, if high-speed trains are expected to operate on the intercity lines, there's probably a strong incentive to keep freight trains off them (and these lines would probably not be going anywhere near the docks).

[The Soodean Imperium]

Does this mean I can safely run freight trains through the city as long as they use the intercity rail corridors? I'm still OK with making outer freight lines that bypass the city and its mountains but running them directly would shave maybe 100km off the distance.

It is possible. Amtrak runs a lot of its intercity services on freight lines, but this basically the reverse of what you were inquiring about, as Amtrak shares lines with freight trains rather than vice versa. It's not really a desirable system though and only exists because Amtrak does not have the funding or political support to build out its own dedicated rail network and freight operators are the only intercity rail services who own a sufficiently large track network. Amtrak has plenty of issues due to this system (and indeed, a lot of its issues can be traced directly back to this shared use model).

Ultimately I think it depends on the expected freight volume and use. Despite its own mountainous terrain, Japan has been willing to build out dedicated freight lines for its most heavily-trafficked routes (e.g. Tokaido freight line), independent of both the regular regional lines and the high-speed intercity lines, and this line runs straight to the Tokyo docks. If demand is sufficient for there to be a dedicated freight line, then one would probably be built. If there is not, then the trains will just be stuck running some indirect and possibly inconvenient routes but it's not a big enough issue to be relevant. In the US it's the reverse because outside of a few new state-sponsored rail programs, Amtrak doesn't have the volume, revenue, or political support to build its own network so it has to rely on a patchwork of freight and state-owned rail lines for its services.

In general, if high-speed trains are expected to operate on the intercity lines, there's probably a strong incentive to keep freight trains off them (and these lines would probably not be going anywhere near the docks).

I'm not talking about having them share the same track along their entire course - once they open up onto flatter terrain, the freight, intercity, regional, and high-speed lines would separate (though freight and regional would still share track on less heavily used lines). Dedicated high speed lines in particular would be a necessity. I only meant trunking them along a single line for part of their course within the city limits, which AFAICT is done in Busan and Tokyo urban areas.

At this point though the idea has evolved to having freight, high-speed, and regional/commuter lines grouped together on adjacent parallel tracks, so that they're not sharing track space per se but are still minimizing the ground area they cover. I may also run the regional/commuter lines on a higher level so they don't interfere with other traffic. And I will also add an alternate freight route on the northern plain which bypasses half of the grouped track through the city. Once outside the city they'll still split up; this is just a temporary move to reduce the space they would take up following alternate routes through the city.

[The Soodean Imperium]

Basically my problem is that most of my rail traffic - commuter, regional, high-speed, intercity, and freight - has to go to the southwest, where the rest of the country is. And with low mountains on either side and a river down the middle, I have to run them through the western half of the city somewhere, or else divert 100+ kilometers north on a route that will require steeper grades and tighter turns.

[The Akasha Colony]

I'm not talking about having them share the same track along their entire course - once they open up onto flatter terrain, the freight, intercity, regional, and high-speed lines would separate (though freight and regional would still share track on less heavily used lines). Dedicated high speed lines in particular would be a necessity. I only meant trunking them along a single line for part of their course within the city limits, which AFAICT is done in Busan and Tokyo urban areas.

I didn't think you were expecting them to share their entire track run, but merging them together in the cities would still create problems with routing (they're heading to different places, presumably) and headway, because train frequency on all lines would be limited by the need to share tracks at certain points, creating bottlenecks. And as far as I can tell, Tokyo's main freight lines seem to run independently of the main passenger lines. And this is despite the fact that as a certain newly-inaugurated president might say, rail freight in Japan is a failing business.

At this point though the idea has evolved to having freight, high-speed, and regional/commuter lines grouped together on adjacent parallel tracks, so that they're not sharing track space per se but are still minimizing the ground area they cover. I may also run the regional/commuter lines on a higher level so they don't interfere with other traffic. And I will also add an alternate freight route on the northern plain which bypasses half of the grouped track through the city. Once outside the city they'll still split up; this is just a temporary move to reduce the space they would take up following alternate routes through the city.

The HSR would probably be elevated too but since it would presumably be limited to only a single line into and out of the city, it wouldn't be hard to accomplish. It would probably be best served by a totally separate line built to its needs though, rather than intentionally trying to group it with existing lines.

Grouping lines might make some sense where they would naturally follow the same path but I'm not entirely convinced they all would. The freight would presumably be heading down to the docks, the commuter rail spiderwebbing across the city to major population centers and commercial hubs, and the HSR heading through whichever station is its designated stopping point in the city. Then again, I don't know much about the layout of this city or its rail networks so there's nothing more I can say. Tokyo certainly has had no issues running single lines wherever needed, and combining them where it is convenient.

Basically my problem is that most of my rail traffic - commuter, regional, high-speed, intercity, and freight - has to go to the southwest, where the rest of the country is. And with low mountains on either side and a river down the middle, I have to run them through the western half of the city somewhere, or else divert 100+ kilometers north on a route that will require steeper grades and tighter turns.

A few mountains never stopped anyone.

[The Soodean Imperium]

At this point though the idea has evolved to having freight, high-speed, and regional/commuter lines grouped together on adjacent parallel tracks, so that they're not sharing track space per se but are still minimizing the ground area they cover. I may also run the regional/commuter lines on a higher level so they don't interfere with other traffic. And I will also add an alternate freight route on the northern plain which bypasses half of the grouped track through the city. Once outside the city they'll still split up; this is just a temporary move to reduce the space they would take up following alternate routes through the city.

The HSR would probably be elevated too but since it would presumably be limited to only a single line into and out of the city, it wouldn't be hard to accomplish. It would probably be best served by a totally separate line built to its needs though, rather than intentionally trying to group it with existing lines.

Grouping lines might make some sense where they would naturally follow the same path but I'm not entirely convinced they all would. The freight would presumably be heading down to the docks, the commuter rail spiderwebbing across the city to major population centers and commercial hubs, and the HSR heading through whichever station is its designated stopping point in the city. Then again, I don't know much about the layout of this city or its rail networks so there's nothing more I can say. Tokyo certainly has had no issues running single lines wherever needed, and combining them where it is convenient.

updated, but still WIP

The Donggyŏng docks (and steelyards and shipyards) are at the city's northeastern edge, and the most active commuter line is the one running along that coast. The capital is in the northeast corner of the country, so most long-distance passenger and freight trains have to exit to the southwest... though, on taking a second look, more freight could be going north than I'd imagined. At any rate, given a city that's longer than it is wide, the most direct route for port freight headed southwest (and all inland manufactured goods bound for export) is to pass through the bottleneck in the western half of the city, as do the main commuter lines and the high-speed train.

I suppose the pedantic answer would be to have the docks relocated further upriver, but in this case it's a matter of path dependency - the docks and shipyards were built there at a time when the main rail line was still beyond the outskirts, as urban planners in the 1870s did not anticipate the explosive urbanization of the 1990s and 2000s.

And on looking at the map again I think I do see a way to reroute freight around the eastern edge of the city while crossing the western hills/mountains at their lowest and narrowest point.

[Questers]

AFAIK freight trains will often simply never go anywhere near the city center itself. They'll divert around the city to the extent possible, especially if they're stopping in which case they'd need to stop at a large freight yard at the edge of town to transfer their goods to trucks or vans or such for last-mile delivery. Their loading gauge often makes the tight tunnels found in major urban areas a bit of a challenge anyway, and in places like the US where cross-country freight trains are often not electrified, traveling through constrained tunnels with a combustion engine locomotive would be a safety hazard anyway.

If they have to run through a city because there are no alternative routes or something, they'll usually be scheduled to move at off hours, often at night. This also tends to keep them clear of peak passenger traffic if they have to share the right of way. A train with good couplers (read: not European ones) can carry a ton of freight so there don't need to be that many departures. Time-sensitive cargo would simply go by truck instead so freight trains can be pushed around the schedule as needed.

Countryside stations tend to see few passenger trains and little passenger traffic so there's little reason to be concerned about headway or the potential safety issues of running a big freight train through a busy station.

That's what I'd suspected. But here's my problem:

VERY WIP

The main shipping areas are in the northeast of Donggyŏng proper (north bank city), and in the east of Gyŏngpo (south bank city). The most active intercity line (both people and freight) would be the one to the southwest, with the one directly due north at a distant second. I can get Donggyŏng port freight to go north along the coastal line, which only passes through a few large towns, and get Gyŏngpo port freight to follow the south peninsula line, which eventually loops around to head southwest, but I can't find an easy way to send Donggyŏng port freight southwest without running the long way through a ~15-million-person city.

This is what led me to consider dedicated freight lines through the city center, which would at least allow me to bypass the busy stations and avoid passenger traffic. These could either be directly adjacent to the existing passenger lines or following a separate course with wider and fewer tunnels. The terrain west of Donggyŏng and south of Gyŏngpo is mildly mountainous (think Beijing not Denver) which makes a loop around the outskirts difficult but not impossible, and I would be willing to follow that path if it's deemed more feasible.

Timeline-wise, the original railway from Donggyŏng port inland would have been built in the 1870s or thereabouts, when the city limits were much smaller and passenger travel was lighter. Though I guess that can't stop me from re-routing rail freight onto new lines in the 1990s, when economic growth brings massive increases in both urban area and trade volume.

Holy shit.

What did you draw that map on?

[The Soodean Imperium]

That's what I'd suspected. But here's my problem:

VERY WIP

The main shipping areas are in the northeast of Donggyŏng proper (north bank city), and in the east of Gyŏngpo (south bank city). The most active intercity line (both people and freight) would be the one to the southwest, with the one directly due north at a distant second. I can get Donggyŏng port freight to go north along the coastal line, which only passes through a few large towns, and get Gyŏngpo port freight to follow the south peninsula line, which eventually loops around to head southwest, but I can't find an easy way to send Donggyŏng port freight southwest without running the long way through a ~15-million-person city.

This is what led me to consider dedicated freight lines through the city center, which would at least allow me to bypass the busy stations and avoid passenger traffic. These could either be directly adjacent to the existing passenger lines or following a separate course with wider and fewer tunnels. The terrain west of Donggyŏng and south of Gyŏngpo is mildly mountainous (think Beijing not Denver) which makes a loop around the outskirts difficult but not impossible, and I would be willing to follow that path if it's deemed more feasible.

Timeline-wise, the original railway from Donggyŏng port inland would have been built in the 1870s or thereabouts, when the city limits were much smaller and passenger travel was lighter. Though I guess that can't stop me from re-routing rail freight onto new lines in the 1990s, when economic growth brings massive increases in both urban area and trade volume.

Holy shit.

What did you draw that map on?

Started with pencil and paper (I feel this is easier when drawing "rough" terrain) then scanned it and traced layers on top in MS Paint.

This also had the effect of magnifying the base image (each "10km" mark was originally one centimeter) so my handwriting looks god-awful

[Gallia-]

Keep the hand drawn borders etc. but kill the writing since you've already digitized that.

It sort of reminds me of the new HOI's for some reason.

Aka Games-That-Are-Worse-Than-Stellaris

[The Soodean Imperium]

Keep the hand drawn borders etc. but kill the writing since you've already digitized that.

It sort of reminds me of the new HOI's for some reason.

Aka Games-That-Are-Worse-Than-Stellaris

I've already traced over the borders and coastlines in Paint, so they'll probably go as well (if only because I made some changes when tracing, e.g. re-routing that river).

Still not sure how to replace the vague "mountain" markings. Elevation lines and shading require too much effort. Ideally I'd like some kind of shaded relief effect on the ridges but that's also a lot of effort.

[Gallia-]

it should be partially hand drawn and partially digital

although i guess you cant say a scanned image is hand drawn

i think you know what i mean though the rough look is qute

[DnalweN acilbupeR]

looks rly good to me tbh

i dont see roughness lol

[The Soodean Imperium]

Honestly I'm not such a fan of the drawn-on look in this context; I only did it so the terrain and city outlines would have a natural rough look.

But I will see if I can retain and expand the "noise" within the urban areas and the profiles of the mountains. I tried moving layers, and it does look better while those are there.

[Hyggemata]

People, how do you like my flag?

[Costa Fierro]

Honestly I'm not such a fan of the drawn-on look in this context; I only did it so the terrain and city outlines would have a natural rough look.

But I will see if I can retain and expand the "noise" within the urban areas and the profiles of the mountains. I tried moving layers, and it does look better while those are there.

What kind of locomotives does your nation operate, out of curiosity?

[Hyggemata]

Honestly I'm not such a fan of the drawn-on look in this context; I only did it so the terrain and city outlines would have a natural rough look.

But I will see if I can retain and expand the "noise" within the urban areas and the profiles of the mountains. I tried moving layers, and it does look better while those are there.

What kind of locomotives does your nation operate, out of curiosity?

Poorly maintained steam locomotives.

[The Soodean Imperium]

Major update, still not quite complete though.

Passenger lines are in dark blue, high-speed lines are in light blue, and freight lines are in orange. At present there are no shared or bundled passenger-freight lines, though historically (i.e. before relief lines were added around the city) there would have been. Intercity (non-high-speed), regional, and commuter trains do share the same track, but as far as I'm aware that's the rule rather than the exception IRL. The commuter stations are at about 10-km intervals on average, which is probably rather far compared to RL lines, but I'm not sure whether to add more in between since the empty spaces are not suburbs but legit smallholder rice fields.

I also added the other main towns scattered around the area, mostly to justify why the commuter stops are where they are. I'm not sure how exhaustive a list it would be, but I'm not ready to place every minor village on a map that was originally just the capital city, and like I said most of the empty space is smallholder agriculture anyway. I added highways too, but this isn't exhaustive either, there would be minor highways beyond those depicted.

I am nevertheless not quite sure what I'm doing, and have mostly been looking at RL cities for reference rather than reading up on the theory of intercity transit systems, so I welcome any feedback on what's there so far.

Honestly I'm not such a fan of the drawn-on look in this context; I only did it so the terrain and city outlines would have a natural rough look.

But I will see if I can retain and expand the "noise" within the urban areas and the profiles of the mountains. I tried moving layers, and it does look better while those are there.

What kind of locomotives does your nation operate, out of curiosity?

Sorry, I only saw this now.

As of the present time, most passenger lines in the country have been electrified; diesel-driven passenger trains still operate in some of the more remote or rural areas of the country, especially in the arid regions of the far west, but certainly all the passenger lines within the boundaries of this map are electric. Beginning in the mid-2000s, the state began building high-speed rail lines, which now connect most major cities. These have their own designated tracks and carry electric trains at top speeds of 250 to 350 kilometers per hour, but they still use standard gauge as opposed to something fancy like Maglev. Freight trains generally use diesel locomotives, and the creation of dedicated freight lines with a broader loading gauge and no overhead wires has brought well cars into more widespread use.

[Costa Fierro]

Passenger lines are in dark blue, high-speed lines are in light blue, and freight lines are in orange. At present there are no shared or bundled passenger-freight lines, though historically (i.e. before relief lines were added around the city) there would have been.

I don't see the southern and northern freight lines being connected, unless you're doing what we (or I at least) suggested vis a vis the rail corridors.

Intercity (non-high-speed), regional, and commuter trains do share the same track, but as far as I'm aware that's the rule rather than the exception IRL.

That's how it works IRL, with even high speed trains sharing the same track to get into major stations. I used the TGV in France about eight years ago and they ran TGV sets on regular rails and the trains often routed into major stations in places like Paris on normal rails also. It's cheaper and better to have one major station catering to all commuter and intercity passenger trains (providing traffic management is good to reduce delays) rather than building two separate stations for normal and high speed trains (as is the case in Avignon).

The commuter stations are at about 10-km intervals on average, which is probably rather far compared to RL lines, but I'm not sure whether to add more in between since the empty spaces are not suburbs but legit smallholder rice fields.

Commuter stations would concentrate principally on where the population is most dense, so suburban areas where there might be a stop every couple of kilometres. The wider metropolitan area is less dense but still a source of significant commuter traffic so it could be a case of having one station in every major population center outside of the capital's main urban area.

[The Akasha Colony]

That's how it works IRL, with even high speed trains sharing the same track to get into major stations. I used the TGV in France about eight years ago and they ran TGV sets on regular rails and the trains often routed into major stations in places like Paris on normal rails also. It's cheaper and better to have one major station catering to all commuter and intercity passenger trains (providing traffic management is good to reduce delays) rather than building two separate stations for normal and high speed trains (as is the case in Avignon).

It's possibly cheaper to share track and stations but not necessarily better. It depends on the routing and the location of the stations.

The Japanese government was willing to build completely separate tracks for the Shinkansen (partly motivated by the need for a separate gauge) but has built completely separate stations or routed high-speed intercity trains to less-busy stations in cases where it was deemed more economical than routing through existing hubs, including in major cities. Notably, it built separate Shinkansen stations in Osaka and Yokohama along the Tokaido Shinkansen rather than route the trains into each city's existing stations. In Tokyo, the Shinkansen serves the preexisting Tokyo Station rather than the much more heavily trafficked Shinjuku, Shibuya, or Ikebukuro stations, which are the major hubs for commuter rail.

Eurostar was forced to route its trains into Waterloo station initially because the British government dragged its feet on the construction of a dedicated high-speed line. This meant the Eurostar trains had to share track infrastructure with commuter trains, which also meant delays during peak hours because the tracks were already at capacity and so Eurostar got bumped in favor of local trains, partly defeating the point of "high-speed rail." With the completion of High Speed 1, Eurostar moved to the much smaller and much less busy St. Pancras, which was nonetheless better located for its projected future services and just as importantly had enough adjacent space to build a new trainshed big enough to house the 400 meter Eurostars. The Waterloo solution was cheaper but not better, and eventually the British government went with the better solution.

Problems tend to arise either when there is not enough passenger volume to justify multiple stations, when the separated stations are not connected to the local transportation network (or when the local transportation network is not sufficiently developed), or when passenger volume is too great for a single station to handle. Avignon's arrangement was probably justified by cost, to avoid having to build an expansion of the existing station to handle additional passenger volume. Tokyo, Paris, London, and other major cities all have enough passenger volume and a sprawling web of mass transit to justify separate stations. They're big enough to justify multiple commuter stations and even separate high-speed rail stations. I can't say for certain, but I'd expect Soode's capital falls more in line with these cities than with Avignon.

[Costa Fierro]

It's possibly cheaper to share track and stations but not necessarily better. It depends on the routing and the location of the stations.

Well it also depends on how much rail traffic there is and how many intercity stations there are needed and whether or not it's economical or indeed, possible to build a new station specifically for high speed trains.

Problems tend to arise either when there is not enough passenger volume to justify multiple stations, when the separated stations are not connected to the local transportation network (or when the local transportation network is not sufficiently developed), or when passenger volume is too great for a single station to handle. Avignon's arrangement was probably justified by cost, to avoid having to build an expansion of the existing station to handle additional passenger volume.

The TGV serves both the TGV station and the regular rail station in Avignon.

Tokyo, Paris, London, and other major cities all have enough passenger volume and a sprawling web of mass transit to justify separate stations. They're big enough to justify multiple commuter stations and even separate high-speed rail stations. I can't say for certain, but I'd expect Soode's capital falls more in line with these cities than with Avignon.

I realize this, but the TGV is also only one high-speed system. Interesting that you mention Paris, because the only separate TGV station in the entirety of Paris is at Charles de Gaulle Airport. Five of the six main stations in Paris are used as hubs for TGV services.

[The Akasha Colony]

The TGV serves both the TGV station and the regular rail station in Avignon.

I am aware. But the construction of Gare d'Avignon TGV coincided with the completion of the LGV Mediterranee which significantly increased passenger traffic along that route, which presumably would have required either expanding Avignon-Centre to handle the traffic or building a separate station.

I realize this, but the TGV is also only one high-speed system. Interesting that you mention Paris, because the only separate TGV station in the entirety of Paris is at Charles de Gaulle Airport. Five of the six main stations in Paris are used as hubs for TGV services.

And?

So far, every nation that's embarked on major high-speed rail programs has used both existing and new stations as appropriate. Sometimes the fiscal and political means, the track layout, and other factors may favor consolidation in existing stations, as in London, New York, and Paris. Other times, it may make a new station more attractive, as in Osaka, Seoul, Aomori, Shanghai, and Avignon. Sometimes it means consolidating all high-speed rail in a single existing facility that isn't a huge local rail hub, like Tokyo Station.

But to say that it's cheaper and better to have a single station as a general statement is, IMO, hard to defend. It varies too much from city to city to be true.

[The Soodean Imperium]

Semi-related question while we're on this topic: is there any precedent for a municipal government converting ground-level railways to elevated ones because the city has grown around them? Or would there be another solution to this? Either way, how would it be done to avoid disrupting rail traffic during construction? As I mentioned earlier, the main passenger lines in both cities were originally laid down in the 1870s-ish as a multi-purpose ground-level line around the outskirts, but it would be nice if I could have them be elevated lines later on when they solely carry electrified passenger trains

Passenger lines are in dark blue, high-speed lines are in light blue, and freight lines are in orange. At present there are no shared or bundled passenger-freight lines, though historically (i.e. before relief lines were added around the city) there would have been.

I don't see the southern and northern freight lines being connected, unless you're doing what we (or I at least) suggested vis a vis the rail corridors.

You're right, they're not

Would it be sufficient to connect them off the southern edge of the map, and adjust their courses to suggest this? It's still tacking an extra 100 kms or so onto the journey, but if the Gyŏngnam line is electrified and elevated it may struggle with tall and heavy well cars passing through all the time.

Intercity (non-high-speed), regional, and commuter trains do share the same track, but as far as I'm aware that's the rule rather than the exception IRL.

That's how it works IRL, with even high speed trains sharing the same track to get into major stations. I used the TGV in France about eight years ago and they ran TGV sets on regular rails and the trains often routed into major stations in places like Paris on normal rails also. It's cheaper and better to have one major station catering to all commuter and intercity passenger trains (providing traffic management is good to reduce delays) rather than building two separate stations for normal and high speed trains (as is the case in Avignon).

Maybe it's hard to see here, but the high-speed line does merge alongside regular passenger trains while moving through the city, and stops at Donggyŏng Main Station. The high-speed trains use standard gauge and are electrified, so they could move onto regular rails during this stage. Though I'd imagined having two sets of track running in either direction down that trunk so that traffic from commuter trains wouldn't interfere as much with the high-speed and express intercity lines.

The commuter stations are at about 10-km intervals on average, which is probably rather far compared to RL lines, but I'm not sure whether to add more in between since the empty spaces are not suburbs but legit smallholder rice fields.

Commuter stations would concentrate principally on where the population is most dense, so suburban areas where there might be a stop every couple of kilometres. The wider metropolitan area is less dense but still a source of significant commuter traffic so it could be a case of having one station in every major population center outside of the capital's main urban area.

Right now I have one station in each population center large enough to be marked red on the map, sometimes two, and occasionally stations in between where the rail line passes a highway or something. But that's still about 5-10 kms between stations on average, compared to 2-3 kms between stations on New York's Harlem Line for example. And I'm not sure if it's worth adding more stops in between given that much of the empty space is smallholder agriculture rather than middle-class suburbs.

I'm also divided over whether to add more commuter stops within the city center, which would increase delays but serve commuters better, or use express service to larger and more widely spaced stations, with the understanding that passengers will use the subway lines spreading out from those hubs.

But to say that it's cheaper and better to have a single station as a general statement is, IMO, hard to defend. It varies too much from city to city to be true.

Literal path dependency

[Purpelia]

Semi-related question while we're on this topic: is there any precedent for a municipal government converting ground-level railways to elevated ones because the city has grown around them? Or would there be another solution to this? Either way, how would it be done to avoid disrupting rail traffic during construction?

Most likely by building a separate new elevated line next to the old one that you keep running and than transferring everything over before decommissioning the old one. You'll probably want to do that anyway with the switch to high speed trains.

[Saint Fedski]

Semi-related question while we're on this topic: is there any precedent for a municipal government converting ground-level railways to elevated ones because the city has grown around them? Or would there be another solution to this?

Based on what's going on in my area of the real world, there's not much. The sheer amount of resources and time it would take is prohibitive. Also, the disruptions would be enormous. As an example: Toronto, Ontario has two elevated highways that are crumbling - literally a matter of time before they collapse. Rebuilding those would cripple the city. Another city, London, Ontario is trying to simply expand an underpass (a road going underneath a rail line) by two lane. Unfortunately there are huge logistical hurdles that need to be overcome: what to do with the rail traffic? what to do with the road traffic on the major artery? The other problem is the work area. It is in a built up subdivision so there is little room for heavy equipment and material staging. The council there has recently taken the rare step of passing a by-law to allow the city to expropriate (eminent domain) a century house for demolition in order to facilitate the work.

Such projects can be done, but the impacts would be huge. It could make for a nice political/social RP or story for your nation though. I'd like to read it, perhaps get involved.

[Saint Fedski]

I'm trying to back story my monarchy. I'm going the rare route of female-primogeniture (first-born female heir) which is difficult enough trying to have realistic birthing years yet not super old monarchs on the throne for a year before they die. The trap I'm falling into is the creation of a dynasty because it's easy enough to go back along the parent-child route. But I'm having trouble with inter-marriage. In real life, houses of royalty and nobility have intermarried thus throne goes from one house to another.

I'm looking to establish a few different houses to break up the dynasty I've created. The future holds an RP with a pretender and a disputed claim to the throne.

Can anyone provide some helpful insight, advice, a hand up etc. in this regard?