Tube Map Central is a website dedicated to the history, design and usability of schematic transport maps. The maps themselves are created to make journeys easier, but Max Roberts, the psychologist behind Tube Map Central and a schematic map designer, points out they can often be unnecessarily difficult to use. We’ve been chatting to Max to find out more about what makes the perfect schematic map.
Image credit: TFL
Schematic maps pop up in cities and towns all around the world, trying to make public transport easier to use by offering the information you require the most, and omitting the stuff you don’t need. With an abstract approach to the actual design of the map though, getting a schematic map perfect is a difficult thing to do, especially as people tend to see things slightly differently.
“I'm interested in lay-theories of effective design,” Max tells us. “Whenever I post a controversial map online, I always get plenty of comments along the lines of ‘this map looks easy to use’ or ‘this map looks difficult to use’. The problem is that people are rarely in agreement, and often contradict each other. Someone must be wrong, but in the absence of usability data, we can't be certain who.”
“People have distinct map preferences in terms of what they believe to be usable, based on aesthetics, expectations, and prejudices,” says Max.
Image credit: Tube Map Central
Designing the best map for the job
“My position is that different networks worldwide have different structures. That means different line trajectories and connections, with the resulting networks fitting different design rules.”
“The task of the designer is to maximise the fit,” adds Max.
So what does make the perfect schematic map? Max explains:
The criteria for usability are:
“Simplicity: Individual lines should have simple trajectories: few bends. What is the point of taking twisting turning reality and converting it into twisting turning zigzags instead.”
“Coherence: How lines relate to each other to give the overall holistic shape of the map.”
“Harmony: Other aesthetic aspects of the line configurations that people will find naturally pleasing (subject to individual differences).”
“Balance: An even density of stations across the pace, no wide-open spaces next to crushed-up areas.”
“Topographicity (a made up word): The map should be a reasonable reflection of reality. Topographical distortion to achieve the above is permissible as long as the distortion does not mislead or conflict excessively with their mental maps of the city.”
“As long as a map can achieve the above, the design rules don't matter.”
Image credit: Stuttgart City Information Site
With those criteria in mind, Max explains how he goes about designing the best schematic map possible:
“My process is to create a design sequence. That is, within a standardised page/font size, explore a network by systematically altering the design rules. For example, the standard London map has four different angles. I would explore the space of possibilities more fully by looking at the very least, two-angle, three-angle, four-angle, six-angle, and any-angle linear maps, plus a freeform bezier curvilinear design and a concentric circles design. The design priority is to maximise the above criteria, and the result is a deeper understanding of the structure of the network, and what design rules enable it to be presented most effectively.”
“There have been some disastrously poor designs created over the years,” says Max, “and they are generally poor for most people. They might differ in their assessments of usability and aesthetics, but I am yet to come across a design that is good for one type of person, bad for another type (e.g. one design is really usable for females, but something very different is more usable for males). That's not to say this couldn't happen in the future, but in general, the worst designs, complex line trajectories, incoherent, unbalanced, distorting, are bad for everyone.”
It’s interesting to see just how much thought goes into some schematic maps, although Max concludes:
“I do wonder sometimes whether designers are really thinking about why schematic maps might help the user. It often seems as though the theory of the designer is that there is something magic about straight lines at certain angles, even if the result is a complex mass of twisting zigzags. Henry Beck's original [London Underground] design wasn't special because it used straight lines at certain angles, it was special because it had so few corners, and didn't distort London beyond people's comfort zones.”
To understand what ticks the boxes for most people, Max is currently carrying out a survey on schematic map design at Tube Map Central. We’ll return to the topic when the results come out! (And do take part, if you haven’t already).
What matters most for you in a transit map?