Isochronic Singapore: A Gentle Introduction to Isochrone Maps

The shape of transport in Singapore.

Isochrone map of London from Mapumental (2006), the map that sparked my interest.

I have a long-standing fascination with isochrone maps. Apart from finding the organic forms alluring, these maps are information dense whilst remaining legible due to its conceptual simplicity. They have also allowed me to recognise the importance of urban mobility, that travel time is more important than physical distance in an urban environment.

Isochrones are akin to topographical contours, but instead of representing elevation they represent travel time. Isochrone maps incorporate isochronic contours at set intervals (e.g. 15-, 30-, 45- and 60-minute intervals) to illustrate the relief and bring shape to the landscape, which have been utilised in transportation planning from as early as 1887.

That said, just like topographical contours, it takes some time to get accustomed to reading these representations. Thus, as an alternative view of the same data, I’ve made a variant which renders the isochrones in 3D as elevations. Below is an example of isochrones emanating out of Bishan.

(Left): Isochrones emanating from Bishan. (Right): The same isochrones rendered as elevation.

‘Ridge lines’ or ‘island’ chains become evident in the 3D rendering, especially towards the North. The peaks of these ‘islands’ align themselves to train stations.

Below are a couple of examples which reveal different patterns within the landscape of public transit in Singapore.

Bukit Panjang: The Central Water Catchment Area is one of the few major natural barriers in Singapore. Starting from the West, one has to skirt around it to get to the central and eastern regions of Singapore, and vice versa.
Flora Drive: ‘Islands’ of faster transit aren’t limited to train stations. In this case, they can also be serviced by express bus routes that travel along the various expressways.
Sungei Gedong Camp: A Reddit favourite, anyone who has served in this camp would know how it feels to be isolated from the rest of civilisation.

Seeing Things Differently

Truth and beauty operator Moritz Stefaner describes data visualisation as macroscope, while Bret Victor in his talk describes building modern tools to assist humans in understanding complex concepts. Both allude towards the idea of allowing us to view the same phenomenon through a different lens or set of lenses to promote understanding.

As mentioned at the start of this writing, I find that one of the most powerful parts of isochrone maps is that it has allowed me to recognise the importance of urban mobility. That not all roads are made the same, nor are all locations within a city equally accessible. There are areas within a city that can be physically near, but inaccessible. And thus improving mobility effectively brings places nearer together.

Further Exploration

Apart from presenting urban mobility in a legible form, isochrone maps can also be used to answer or explore questions such as:

  • Where’s an accessible location to live or work?
  • What’s the impact of adding a new train line or bus route?

Or they can serve as a point of departure to begin to answer these questions:

Try out the interactive demo at https://isochrone.swarm.is/ or play with the 3D variant over at https://isochrone.swarm.is/3d/.

Questions or comments? Reply below or find me at yang@swarm.is or on Twitter @yinshanyang. Thanks for reading!