Mapping London’s Cycling Census Dataset


The London Cycling Census Map is an interactive map I’ve created, showing traffic flows on key corridors in central London. The counts were collected by Transport for London in around 170 locations, in April. TfL released some sample statistics from the dataset in a report published on their website, but the original dataset was not released – however Andrew Gilligan, the Greater London Authority’s cycling commissioner, obtained the data and forward it on to a number of people, including (indirectly) me. I took the data, consolidated it, and created this map. The most tedious bit was pointing the arrows in the right direction!

There are three time periods for which you can show data: AM Peak (7am to 10am), PM Peak (4pm to 7pm) and All Day (which is, I believe, a 24-hour sample.) which is from 6am to 8pm. The locations chosen are generally ones where high numbers of cyclists travel, so some roads which have high numbers of other vehicles, but not bicycles, e.g. Oxford Street, are not included.

Cycling along key corridors in London is highly time dependent – in the below extract, morning (red) and evening (green) flows for cyclists are compared. Cyclists generally travel away from Clerkenwell, to the east and the west, in the morning, returning to it in the evening. The other travel modes generally don’t show this directionality on this road – cars in particular generally travel in both directions during both peaks. I would hypothesis that the cyclists are accessing this road from Goswell Road, which unfortunately wasn’t included in the census.


So what does the data show?

  • There are several roads where there are more bikes on the streets than any other type of vehicles.
  • Bicycle flow is highly direction, unlike that for most other forms of transport.
  • There are certain routes which are popular with certain kinds of traffic. There are four main east/west corridors in central London. Cars dominate the north-most (Euston Road) and the south-most (Victoria Embankment) ones. Taxis heavily use Holborn, while cyclists mainly use Old Street/Theobold’s Road. You can see all four of these corridors in the map extract at the top of this article.
  • Equivalent north-south links show little separation of vehicle types.
  • Elephant & Castle remains a complicated junction with large numbers of cyclists and buses, depending on the direction, road and time of day.

A note on the arrows

The map uses the vector styling capabilities of OpenLayers, with a custom SVG “arrow” symbol. Symbols in OpenLayers are always positioned with their centre over the location point, so to have them pointing away from the location, I had to add a hidden stalk to each arrow – you can see the stalk when clicking on it. My custom SVG for the arrows is:

OpenLayers.Renderer.symbol.arrow = [1, 0, 0, -3, -1, 0, 0, -0.5, 0, 3, 0, -0.5];

I’m using 0, 0 as the point on the arrow that corresponds to the underlying location – but it doesn’t need to be that, i.e. the location of 0, 0 does not affect where OpenLayer actually pins your symbol on your point location.

And finally…

Red arrows are taxis, blue arrows are buses. Proof, perhaps, of the oft-quoted saying that it’s a battle to find a London taxi driver willing to go south of the river:


The map was created as an output of EUNOIA, a European Union funded project to model travel mobility in major European cities using novel datasets. UCL CASA is the UK university partner for the project.

You can view the map here.
View alternative version of the map – uses OpenCycleMap as a basemap.
Download the data here which I have augmented with bearings.