Paris vs Tokyo: the two different models for express commuter rail stopping patterns

A commuter at Tokyo's Shinjuku station. Image: Getty.

Many cities have large commuter rail networks, which function as urban rapid transit and extend into the suburbs. They use mainline rail rather than separate subway tracks, but are identical in other respects to conventional metro systems: urban stop spacing, frequency, and fares are all within the range of metro systems.

The biggest systems are in Japan, where Tokyo and Osaka carry the vast majority of their public transport passengers on commuter trains and not metro trains. In Europe, the biggest system is the Paris RER, while in the German-speaking world all major cities have S-Bahn networks.

But while the concepts are all broadly similar – mainline trains serving the suburbs share tracks in the core, so as to provide metro-like frequency – the stopping patterns vary.

First, some regional rail systems run express trains, whereas others are all local. The Munich and Berlin S-Bahns only have local trains. In contrast, the Paris RER and the Tokyo commuter rail network combine local and express trains – sometimes on four tracks, and sometimes on two, using the schedule to avoid conflicts.

Usually, systems that run express trains are bigger than systems that do not, but there are exceptions: Copenhagen's S-Train has express trains on most branches, and the Zurich S-Bahn has express trains on some lines as well.

On systems that are not modernised, express trains are especially common. That’s because the traditional function of commuter rail is to connect the suburbs with city center at rush hour; local services, connecting the suburbs with each other and not just with the city, are less important.

As a result, American commuter lines, even ones with very little ridership by European or Asian standards, generally have express trains: each stopping pattern might only get 1 or 2 trains per hour at rush hour. So do a few European branches, for example some of the outer commuter lines in Paris, not connected to the RER. Since these lines carry few riders, the important distinction is between different local and express patterns on busy lines that run frequently all day.

There isn't much to say about local trains, which (mostly) stop at every station. Express trains are more complex, and there are two ways to run them: one common in Paris, the other common in Tokyo. The Parisian model is to have long central segments with only two tracks, on which every train makes every stop. (In London, Crossrail is planned to follow the same pattern.) Tokyo’s railways have four-track segments, and express trains skip some stops even in the core.

Tokyo-style express trains may skip fewer stops in the centre than in dormitory communities, but they still skip even some central areas. On the eight-track main between Tokyo and Shinagawa Stations on the Tokaido Line, for example, the local Yamanote and Keihin-Tohoku Lines make all four intermediate stops; but the express Tokaido Main Line and Yokosuka Lines only make one intermediate stop, at Shimbashi. Central Tokyo stretches roughly between Tokyo Station and Shimbashi, and there is one station between them, Yurakucho, with transfers to four Tokyo subway lines. But in the judgement of rail planners, it made sense to skip this station, and for express trains to serve just one in every so many stops on the inner part of the line.

In Paris, no such thing service exists: the central tunnels only have two tracks, so it is hard to arrange local and express trains on them. Even on the few segments of the central network that have four tracks, such as part of RER C, there is no stop skipping. The transport authorities judge it best to have every commuter train make every stop within the city proper, which extends about 5 km out of the center.

Conversely, in the suburbs, Paris does mix some local and express trains on two tracks: the RER B runs 12 trains per hour off-peak – just enough room for trains which run non-stop between Gare du Nord and Charles-de-Gaulle Airport, and some express trains in the southern suburbs.

The Parisian approach ensures that the RER can function as high-frequency trunk lines within the city proper. The RER A averages a stop per 2.5 km on the central trunk, and the RER B and C a stop every 1.2-1.3 km (the other two RER lines, the D and E, only make three city stops each). The Metro averages a stop every 500 meters, of course – but nonetheless, 1.2-1.3 km is well within the range for international metro systems, comparable to the spacing of stations on the London Underground. The central Crossrail trunk will average a stop every 1.6 km – wider than the Underground but not much more so.

In Tokyo, of course, the commuter rail frequency in the core is even higher, since the inner lines are all at least four-tracked. But farther out, there are express and local trains mixed on two tracks, with timed overtakes, using the legendary punctuality of Japanese railways to schedule trains to avoid conflicts. The result is that the express routes have quite wide stop spacing, which permits higher speeds, approaching 60 km/h on the Tokaido and Tohoku Main Lines.


A smaller city, with trunk lines not as full to capacity as in Tokyo, Paris, or London, could mix local and express trains even at rush hour. In Tokyo, local and express trains are mixed on some lines on the shoulders of rush hour (but not at rush hour, when trains arrive every 2 minutes); it is unclear what the absolute upper limit of this system would be, but it appears to be in the range of 15-20 trains per hour. In cities without Japanese punctuality, the limit is about 12 trains per hour: a local train and an express train each coming every 10 minutes, with an overtake every 6-8 stations.

Such cities have a choice. The Paris approach works very well for Paris, and the Tokyo approach works very well for Tokyo. There is always a tradeoff in mass transit between narrow stop spacing for service to more places, and wide stop spacing for higher average speed.

The two different approaches for commuter rail express stopping patterns display a related tradeoff, between higher frequency to all stations and higher average speed at express stations. Which of the two approaches is better depends on local factors. These include city size and density (more sprawl encourages the faster Tokyo approach, more density encourages the more frequent Paris approach); punctuality (better punctuality makes mixing local and express trains on two tracks easier); and how important it is that suburban commuters be able to reach every urban station, rather than just a few major stations.

There is no inherent better choice. The tradeoff is not that one option is more beneficial but more expensive, but rather that the two options have different benefit levels, depending on local conditions.

Those conditions can vary widely between cities, even in the same country. A smaller French or British city might find that its home and job distribution makes the Tokyo approach better, and a smaller Japanese city might find that the Paris approach works better for it.

Cities anywhere might even find that the German approach of not having any express trains works best. This means that planners should consider all stopping patterns, and not just default to what is familiar from nearby cities.

Alon Levy blogs at Pedestrian Observations and tweets as @alon_levy.

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A nation that doesn’t officially exist: on Somaliland’s campaign to build a national library in Hargeisa

The Somaliland National Library, Hargeisa. Image: Ahmed Elmi.

For seven years now, there’s been a fundraising campaign underway to build a new national library in a nation that doesn’t officially exist. 

Since 2010, the Somali diaspora have been sending money, to pay for construction of the new building in the capital, Hargeisa. In a video promoting the project, the British journalist Rageeh Omar, who was born in Mogadishu to a Hargeisa family, said it would be... 

“...one of the most important institutions and reference points for all Somalilanders. I hope it sets a benchmark in terms of when a country decides to do something for itself, for the greater good, for learning and for progress – that anything can be achieved.”

Now the first storey of the Somaliland National Library is largely complete. The next step is to fill it with books. The diaspora has been sending those, too.

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Some background is necessary here to explain the “country that doesn’t exist” part. During the Scramble for Africa of the 1880s, at the height of European imperialism, several different empires established protectorates in the Somali territories on the Horn of Africa. In 1883, the French took the port of Djibouti; the following year, the British grabbed the north coast, which looks out onto the Gulf of Aden. Five years after that, the Italians took the east coast, which faces the Indian Ocean.

And, excepting some uproar during World War II, so things remained for the next 70 years or so.

The Somali territories in 1890. Image: Ingoman/Wikimedia Commons.

When the winds of change arrived in 1960, the British and Italian portions agreed to unite as the Somali Republic: a hair-pin shaped territory, hugging the coast and surrounding Ethiopia on two sides. But British Somaliland gained its independence first: for just five days, at the end of June 1960, it was effectively an independent country. This will become important later.

(In case you are wondering what happened to the French bit, it voted to remain with France in a distinctly dodgy referendum. It later became independent as Djibouti in 1977.)

The new country, informally known as Somalia, had a difficult history: nine years of democracy ended in a coup, and were followed by the 22 year military dictatorship under the presidency of General Siad Barre. In 1991, under pressure from rebel groups including the Hargeisa-based Somali National Movement (SNM), Barre fled, and his government finally collapsed. So, in effect, did the country.

For one thing, it split in two, along the old colonial boundaries: the local authorities in the British portion, backed by the SNM, made a unilateral declaration of independence. In the formerly Italian south, though, things collapsed in a rather more literal sense: the territory centred on Mogadishu was devastated by the Somali civil war, which has killed around 500,000, displaced more than twice that, and is still officially going on.

Somalia (blue) and Somaliland (yellow) in 2016. Image: Nicolay Sidorov/Wikimedia Commons.

The north, meanwhile, got off relatively lightly: today it’s the democratic and moderately prosperous Republic of Somaliland. It claims to be the successor to the independent state of Somaliland, which existed for those five days in June 1960.

This hasn’t persuaded anybody, though, and today it’s the only de facto sovereign state that has never been recognised by a single UN member. Reading about it, one gets the distinct sense that this is because it’s basically doing okay, so its lack of diplomatic recognition has never risen up anyone’s priority list.

Neither has its library.

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Rageeh Omar described the site of the new library in his fundraising video. It occupies 6,000m2 in the middle of Hargeisa, two minutes from the city’s main hospital, 10 from the presidential palace. In one sequence he stands on the half-completed building’s roof and points out the neighbours: the city’s main high street, with the country’s largest shopping mall; the Ministry of Telecoms that lies right next door.

This spiel, in a video produced by the project’s promoters, suggests something about the new library: that part of its job is to be another in this list of landmarks, more evidence that Hargeisa, a city of 1.5m, should be recognised as the proper capital of a real country.

But it isn’t just that: the description of the library’s function, in the government’s Strategic Plan 2013-2023, makes clear it’s also meant to be a real educational facility. NGOS, the report notes, have focused their resources on primary schools first, secondary schools second and other educational facilities not at all. (This makes sense, given that they want most bang for their buck.)

And so, the new building will provide “the normal functions of public library, but also... additional services that are intentionally aimed at solving the unique education problems of a post conflict society”. It’ll provide books for a network of library trucks, providing “book services” to the regions outside Hargeisa, and a “book dispersal and exchange system”, to provide books for schools and other educational facilities. There’ll even be a “Camel Library Caravan that will specifically aim at accessing the nomadic pastoralists in remote areas”.

All this, it’s hoped, will raise literacy levels, in English as well as the local languages of Arabic and Somali, and so boost the economy too.

As described. Image courtesy of Nimko Ali.

Ahmed Elmi, the London-based Somali who’s founder and director of the library campaign, says that the Somaliland government has invested $192,000 in the library. A further $97,000 came from individual and business donors in both Hargeisa and in the disaspora. “We had higher ambitions,” Elmi tells me, “but we had to humble our approach, since the last three years the country has been suffering from a large drought.”

Now the scheme is moving to its second phase: books, computers and printers, plus landscaping the gardens. This will cost another $175,000. “We are also open to donations of books, furniture and technology,” Emli says. “Or even someone with technical expertise who can help up set-up the librarian system instead of a contemporary donation of a cash sum.” The Czech government, in fact, has helped with the latter: it’s not offered financial support, but has offered to spend four weeks training two librarians.  

Inside the library.

On internet forums frequented by the Somali diaspora, a number of people have left comments about the best way to do this. One said he’d “donated all my old science and maths schoolbooks last year”. And then there’s this:

“At least 16 thousand landers get back to home every year, if everyone bring one book our children will have plenty of books to read. But we should make sure to not bring useless books such celebrity biography books or romantic novels. the kids should have plenty of science,maths and vocational books.”

Which is good advice for all of us, really.


Perhaps the pithiest description of the project comes from its Facebook page: “Africa always suffers food shortage, diseases, civil wars, corruption etc. – but the Somaliland people need a modern library to build a better place for the generations to come.”

The building doesn’t look like much: a squat concrete block, one storey-high. But there’s something about the idea of a country coming together like this to build something that’s rather moving. Books are better than sovereignty anyway.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason. 

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