Bathampton - transiting traffic

Building on the previous blog post, I've extracted some 13,000 vehicle transits of Bath on 31 October 2017 from data provided by BathHacked. (These are all the entries and exit again within 30 minutes, through the 'radial 1' on the map shown before.)

A chord plot, using the great circlize package in R is a good way to show these flows. The counts around the edge are transit entries or exits - so the total is 26,000. Direction is indicated by the slight point/arrowhead.

You can see a big influence of the Batheaston bypass in the flow between North (Lansdown and Swainswick (dual carriageway)) and East (Box Road & Bathford). That's expected.

But I'm really surprised that the very large majority of vehicles entering or leaving Bathampton (near Dry Arch) and transiting Bath are also heading to, or coming from the North. Around 700 heading North, and 1,000 heading South. Very little traffic transiting and heading West, for example.

Can this be correct? More checking needed, I think.

(Note that one vehicle might generate more than one transit in the day