A continuation of this post.
The core branding idea of the Paris RER is a really powerful one. Here's how it used to be presented, as a consistent citywide product (click to enlarge; full-size map here):
Focus on the red line, Line A. Its a single line across the center of Paris with branches on both ends. The common segment in the center has a high enough frequency that you can use it as though it were a metro line, while the branches are less frequent but still very good service for outer suburbs. The branches are called A1, A2, etc, but the common segment is just Line A.
This branding scheme is a good example of the principle that simple services should be presented in ways that make their simplicity clear. Customers should be presented with complexity only if they need the more complex information, such as to select the correct outer branch for reaching an outer-suburban destination. So on the RER, if you need to go to, say, Euro-Disneyland in Marne-la-Vallée, you need to select the suburban branch called A4, but if you just want to ride on the metro-like segment within the core of Paris, you just need to remember Line A. The system provides one level of nomenclature for describing the simple common segment which is all that a huge percentage of riders will use, and a second more complex layer only for the people who need that complexity.
Actually, there are FOUR tiers of information here in a clever hierarchy, all designed to ensure that you don't have to learn more information that you need to do what you're going to do:
- A Métro route number signifies a simple, frequent line that doesn't require you to learn much more, apart from riding it in the correct direction.
- An RER route letter such as Line A identifies the common RER segment across the core of Paris and invites you to use it exactly as if it were any other metro line, without caring about its branches.
- Odd vs. even numbered branch numbers on the RER indicate different directions on the common segment. On Line A, for example, odd-numbered branches are all in the west, even numbered ones in the east, so as you get to know the service, the branch number tells you which way the train is going on the central segment. Even if you're not riding onto a specific branch, this can be useful, as redundant 'confirming' information, to assure you that you're riding in the correct direction. This is important as it's very easy to lose your sense of north (if you ever had one) in the warrens of underground stations.
- Finally, the individual branch numbers are needed ONLY if you're headed for a specific suburb beyond the branch point, such as Marne-la-Vallée.
The principle is that this is a progression from simple to complex. The point of this hierarchy is not to lead customers all the way through, but exactly the opposite: to enable them to "get off," ignore the remaining layers, as soon as they have the information they need.
But alas! SNCF has demolished this system on the RER lines that they operate (C, D, and E) and replaced it with something that requires the customer to learn much more complexity. While the letters are still there, they are receding in the information system. RER branch numbers (C2, C3 etc) have disappeared entirely on the SNCF-controlled lines. Instead, users are confronted with a single line number (C) and then the names of various possible endpoints. Sometimes, as on this sign, the endpoint appears without even a line number -- a throwback to how the Métro was presented before line numbers were introduced in the 1970s.
Endpoint-based nomenclature is common in many rail systems, but it carries several nasty problems when used without line numbers or names:
- Every time you extend a line, you're renaming it.
- Endpoint nomenclature in the absence of even a line number (as in the disturbing sign above) can create confusion between different lines that travel to the same endpoint, but by different routes.
- Endpoints are a lot more information to remember, especially if you're on a line that could branch to several possible endpoints and you only need to know that you're going the right direction. By contrast, the C2, C3 system allowed passengers to quickly recognise the direction of the train (odd vs even) without caring which branch it went to.
This is especially a problem on Line C (yellow on the map above) because one of this line's southeastern branches, the C8, wraps around to the west to end at Versailles, which is also served by western branches on the same line. So if passengers must rely on the names of endpoints to figure out which way they're going on the core Paris segment, 'Versailles' is going to be misleading. (Sydney readers may be reminded of the experience on Cityrail at Lower North Shore stations, where trains in both directions can have the final destination 'Hornsby.') The C8 designation was more useful in helping customers see that this is one of the eastern branches -- and thus denotes a train going east through the Paris core -- despite its ultimate endpoint in the west.
So here's what I'd like to posit based on the RER story, and many others. As always, please argue with me.
- An effective customer-oriented system of nomenclature focuses on distinctions that will matter to the customer, such as indications of frequency and relative speed vs stop-spacing.
- An especially good system provides levels of detail couched so that the customer is not forced to learn more detail than she actually needs. The four levels of nomenclature in the Paris rapid transit system do this especially well, but focus on this is being lost on the SNCF's RER lines, possibly as a result of an over-emphasis on promoting SNCF as the operator of the service.
- In an environment without direct customer choice between competing operators, such as urban rapid transit, operator logos seem mainly to serve the needs of institutional ego. Meanwhile, these logos can distract from, and thus undermine, efforts to present a complete citywide system of routes that work together for the customer. (There are a few exceptions to this principle in other cities; for example, in the era when New York City had competing subway companies running under parallel Manhattan avenues, these lines were so close together that a customer really could choose between them for the same north-south trip, but that's clearly the exception rather than the rule in urban transit.)
- There is nothing wrong having a brand that unites and integrates all the commuter rail services in the Paris suburbs, as Transilien purports to do. The only problem with this brand is that it currently belongs to SNCF. I hope that SNCF is encouraging RATP to use the same brand on its own RER services, so that it can come to represent the entire network serving trips in the Paris region.
- Finally, getting nomenclature and branding right is hard, especially where there are multiple operators and/or agencies who like to see their logos out there. Most cities I've worked in don't try to do anything as sophisticated as the original RER nomenclature system, or to extend it across so many services. Paris current presents some nomenclature problems, but these are problems only compared to the very high standard the city has set for itself. The question for other cities is really about how far they want to aspire in the direction of comprehensive legibility, and if so, what they can learn from the Paris experience, both good and bad.