Everyone has their own way of remembering a special place they have travelled to; it may be a photograph capturing a moment, or a souvenir that will be proudly displayed on the shelf for decades to come. For me, being a cartography and public transport enthusiast, it is often about redrawing the metro diagram of a city and recalling my journeys along the way.
However, I have not had the pleasure of visit Seoul, the capital of South Korea, thus far. So, my drawing of this diagram isn’t a homage to a trip filled with happy journeys. No, this is the first time I’ve been compelled to draw a metro diagram because … well, just look at this thing:
This is a screencap of the official English version of the Seoul metro network diagram. Yep, this is legit.
The Story, and the Diagram
A month ago I was aimlessly browsing subway maps from large networks around the world (as cartography nerds do) and I stumbled upon this thing. Me eyes entered a state of visual arrest. This diagram is just so problematic on so many fundamental aspects. To start with:
1. Station names appearing over the lines in multiple places, making it hard to read.
2. The designer has chosen to adopt the relatively unconventional 30 / 60 / 90 degree angle for the lines (probably to compress the diagram and reduce the amount of curves required for what is a very messy, curvy, non-grid system), but kept the text at a 45 degree angle, making for a jarring and inconsistent visual experience.
3. Where the designer ran out of options, however, vertical lines are used, adding another distracting visual element.
4. No curves!
5. The spacing between stations is incredibly inconsistent and bears no semblance to the actual distance. This makes it hard to judge how far apart are the stations in reality. (Part of this appears to be due to a desire to pull all lines to have an end on either the right or left edge of the map for ease of identification – but results in some ridiculous distortion. For example, look at the way lines 5 and 9 are depicted on the left, compared to Gyeongui-Jungang Line – the latter covering a much longer distance, not that you can tell from the map.)
6. The text is compressed quite badly in many places in an effort to make the station labels fit, but this makes the text difficult to read.
7. The line colours chosen don’t stand out enough from one other. Line 1 and Sillim Line look to be almost the same shade of dark blue. Line 3 and Incheon Line 2 look to be the same shade of yellow. In fact, it you look closely, Line 1 has interchanges with a noticeably different and darker shade of blue to the line colour itself.
8. There is no geographical anchor and no visual focal point, so the map is just hard to use and navigate. Given Seoul defines itself based on whether a location is north or south of Han River, surely it would be useful to at least show this.
Note the very similar colour chosen for Metro Line 1 and Sillim Line - and the fact that the colour used to show Line 1 and the stations on Line 1 is noticeably different...
The diagram is so stylized and distorted that it would be near impossible for the design to accommodate the many additional extensions that will come online in the next few years.
And then one looks deeper into the design language used for the system. It has left my head shaking.
Seoul, like many large Asian metro networks, has adopted the (very good) practice of giving each line a letter / number and each station a number as well, which greatly promotes ease of wayfinding. However, the way this has been represented on the map is… baffling:
Line Identifiers
Line identifier 101 – each line should have a unique identifier.
Look at the number of lines with an identifier of “G” or beginning with “G”. Look at the number of lines with an identifier of “S” or “I” (which is going to be easily confused with “1” as well…). What gives?
I imagine that the answer is that the designer simply looked to the beginning of the name of each line and took that letter. And the trouble is that many of Seoul’s rail lines have a name beginning with “Gyeong”, referring to the capital in Hanja, being an old name for Seoul. Within the Seoul Capital Region network, there are no less than six “Gyeong” lines – Gyeongui, Gyeongin, Gyeongbu, Gyeonggang, Gyeongwon and Gyoengchun.
But no, the solution cannot be to assign the code “G” to all of these lines, especially when there are also other lines beginning with G to add to the confusion, including the Gimpo Goldline.
Line Identifier 102 – the line identifier should match the station code
So the logic goes, the line identifier is carried over to the station code, so the passenger can figure out, for every station, the line it is on and how far along the line they’re on. Example, “G07” should be referring to the “G” line and the seventh station on the line.
However, the designer realized that with so many lines having the same letter code, this would not work. After all, to adopt the logic would mean that there are many “G07”s around. So, instead, they assigned lines with a different line identifier for the purpose of station numbering. But gosh that’s just confusing.
For example, both Gyeongchun Line and Gyeonggang Line are “G” lines, but one has a line identifier of “P1” for station numbering purposes, while the other is “K4”. Why not just give Gyeongchun Line code P1 in all respects and Gyeonggang Line K4 and make it consistent?
Line Identifier 103 – show the station code for each station on the diagram
It goes without saying that the station code is pretty important for wayfinding, especially for novice travellers who may not know their way around the city. This makes the decision to omit the station code from all interchange stations on the diagram incredibly baffling. For some unknown reason, the designer substitutes the station code with the line code instead. Yes, this does make it easier to identify which lines are interchanging, but that can be done using a well-thought-out station coding system anyway?
The problem is especially serious for lines that are basically express lines that stop at multiple consecutive interchanges. For these lines the map basically omits the station code. Case in point: Shinbundang Line (line code: S, line code for station numbering: D) or the Airport Express (line code: A).
Good luck figuring out what's the station code for stops where lines interchange! (Note you can't see any station codes on this section of the Shinbundang (S) line at all, as all of the stations are interchanges...)
Line Identifier 104 – the line and station code should reflect the current service patterns, and not the historical service patterns
This is a problem for the Korail-operated commuter lines (i.e. the “Gyeong” lines referred to above), because these have a long history but don’t operate as they used to, having undergone a number of mergers and re-routing over time.
(And this is not a problem unique to Seoul either – JR East also suffers from similar challenges in coding and numbering its Tokyo Commuter Rail network.)
The problem manifests itself in the way Gyeongui-Jungang Line is presented. Since the completion of a section of track between Gajwa and Yongsan, the two formerly separate lines now operate as one. However, each has retained its historic station numbering (with Jungang Line section bearing “K1” and Gyeongui Line section bearing “K3”), which is just plain confusing when the line operates as one unit. So you end up going from Ichon (K1-11), then Yongsan (K1-10) to Hyochang Park (K3-11) and Gongdeok (K3-12).
Interestingly, when Suin-Bundang Line merged to form one continuous service, the entire line was given one unified station code of “K2”. So, it is unclear why the designers were able to get this right for one line, but not the other.
My call to action... to myself!
Okay, enough criticism. The fact is, Seoul’s Capital Region is huge, and it is complex. Unlike some of the other newer metro systems to have developed since the 1980s (a good example would be those in Beijing and Shanghai), Seoul’s system is not a basic grid. Instead, it resembles Tokyo’s noodle-like mess, probably designed in a way that connects as many important places as possible on one line, rather than creating a network that is simple and easy to navigate.
The shape of the network is also difficult element. Seoul’s network is a very elongated one. You have a very dense core network within Seoul City itself, surrounded by a ring of suburban lines starting from Incheon to the west, then moving south-east to Suwon and Dongtan and Hanam to the east. You then have the Korail commuter rail through services that extend very deep to all corners of the map except the west (it’s all water on that side, after Incheon). This is going to, inevitably, mean lots of compromise on geographical accuracy, lest you end up with a diagram with lots of empty space – plus a very dense core.
So, I know this diagram is not an easy one to draw. And I know that it is easy being an armchair critic. I decided – as any righteous cartography nerd would – that I should put my South Korean won where my mouth is and draw my very own version of this diagram. And in doing so, here is the first time ever that I have drawn a metro diagram of a city I have not visited, out of sheer frustration with its official metro diagram.
I don’t profess to the claim that this map is perfect by any means, but I hope you’d agree that it is a not insubstantial improvement to the official map.
Principle 1: declutter the map
For this map, I have stuck with the tried-and-trusted approach of using 45-degree angle lines throughout. It is less space efficient than the official map for sure, but it does makes everything fit together in relative spatial harmony.
Principle 2: keep the lines straight
Similar to my usual approach to diagrammatic cartography, I have sought to minimize the number of unnecessary curves so the diagram user can follow their route easily. That said, I still had to resort to a few bumps and kinks here and there. My effort in this regard was not perfect.
There are two bumps and kinks to Metro Line 5 that really bothered me but I couldn't quite avoid them. Note Singil (5-25) and Euljiro 4-ga (5-35)
Principle 3: create a point of visual focus and an identity that reflects the location
This is something I try to do for each diagram I draw but not every system lends itself to this principle. Seoul’s sprawling and messy network was a struggle. The best I came up with is to create a large rounded rectangle for Line 2 metro, which puts the bulk of the core of Seoul in frame, similarly to how Line 4 metro encircles Shanghai and the Yamanote Line (JY) encircles Tokyo.
The symbol of Korea is the taegeuk, a circle with either two or three colours – a dark blue, rich yellow and a dark red. In older versions of the official subway map for various Korean cities, interchange stations are often shown with a taegeuk (which probably perpetuated the odd decision to this day to not show the station code for each line at the interchange). I didn’t want to re-introduce the taegeuk into the design language of the diagram itself, but I did include one as a decorative element on the edge of the map and incorporated the colours into the banner.
Principle 4: implement a sensible line and station numbering system, and show it clearly
The diagram is accompanied by a revamped line and station numbering system that aims to overcome the shortcomings with the current approach based on the following principles:
Each form of rail transport can be identified by: (a) the shape / design of line shield; (b) the line code; (c) a distinct pictogram; and (d) the style of the line itself, as follows:
Metro lines that operate as a through service to commuter rail lines retain their number in the through service section for ease of continuity, but the line is depicted as a commuter rail line in all other respects. A symbol on the map depicts when the line transitions from being a metro line to a commuter rail line.
Station and line numbering has been revamped to avoid some of the confusing aspects of the current scheme:
1. Each branch line exceeding one station in length will have an “A” suffix. For example, the new Hanam branch line to Metro Line 5 is depicted as 5A.
2. If the branch line operates as an independent shuttle service, the station numbering will restart at 01. For example, the two branches of Metro Line 2 are independent of the main line, so branch 2A and branch 2B have their own station numbering. By contrast, branch 5A services continue into the main line, so the numbering continues as well.
Illustration of the different approach to station numbering in action - note the difference between branch for Metro Line 2A, which operates as a separate line altogether, and Metro Line 5A, with through services to the rest of Metro Line 5.
3. To avoid having multiple lines with the same line code, many lines have been renamed based on the principle of [form of rail -> number]. No more multiple “G” lines and no more situations where the line code does not match the station numbering scheme. So, on this basis:
And yes, the station numbering is shown for each station on the diagram, especially interchange stations!
Principle 5: show useful information where possible
The diagram includes some additional information not shown on the official diagram, adopting a similar approach to my diagrams for Tokyo and the Kansai region. Lines that operate express and limited express services have their service patterns indicated by a colour-coded dot to the right of the station label.
The complicating factor is that Metro Line 1 – which is a gargantuan amalgam of multiple commuter rail lines, some (but not all!) of which feed into the relatively short metro line section – has multiple different express and limited express services for each of their branches. Hence, I have included a separate diagram to show how it all works, as well as differently coloured dots to show different variants of their express and limited express services.
(It would have been ideal to show Metro Line 1 as at least 2, if not 3 different lines, but the brand identity of Line 1 is quite strong, so I thought it would be better to keep it as is.)
The map also includes a small inset that shows the high-speed rail network in South Korea.
Thanks for reviewing. I look forward to any feedback and comments you may have! Leave them here, or drop me a note at itsbernie81@gmail.com. If you’re keen on architectural and landscape photography, you can also check out my work at Instagram, handle @itsbernie81
A side-by-side comparison to wrap things up
