John Calimente of re:place magazine writes about The Colourful Buses of Seoul
This is great:
In 2004 the Seoul Metropolitan Government completely overhauled their Ilban, or city bus system. Instead of replacing the buses themselves, though, they went with a different approach that consisted of 5 key changes:
1) Bus routes were simplified
2) Four bus categories were created, each with a different colour scheme (red, blue, yellow, and green);
3) Route numbers were changed so that they explained both the origin and destination of the route, based on a district numbering system;
4) A flat-fare system was implemented and integrated with the subway system;
5) Real-time communication systems were installed so that transit riders could check arrival times by cell phone.
The colouring scheme goes a long way towards helping riders know exactly where their bus is going. It's very simple. Blue buses travel long distances on major arterial roads, serving more than 2 districts, and run in median bus lanes when they get close to the centre of the city (this video shows a blue bus entering a separated median lane). Green buses operate as feeder buses to the 8 lines on the subway system and are run by private companies. Red buses are express routes with limited stops connecting major suburban towns to the central city. And yellow buses are circular routes that travel between the major destinations in the central city. Blue and red buses are the same price, while the red (suburban) buses cost more and the local yellow buses less.
But the addition of a route numbering system that actually has explicit meaning is something every transit system should adopt. First they divided Seoul into 8 numbered zones, starting at 0 in the downtown core and giving the surrounding zones numbers 1 through 7.
Then they used these zones as part of the route numbers. Blue buses have three-digit route numbers. The first number indicates the origin zone and the second number the destination zone, with the last number the bus ID number. So if you encounter bus #048, for example, you know it travels from downtown (zone 0) to zone 4. Red buses put a 9 in front to indicate that these are suburban routes, while yellow buses have only two numbers, since they stay within the same zone.