UK: How do you get maps of council locations on Google maps? (Like twitter does)

Question

On twitter, on a geotagged tweet, it now says something like: From North hertfordshire, hertfordshire

And when clicked you see a map, with a polygon showing the area of north hertfordshire. They seem to have done it for all councils in the UK, rather than cities or town s.

Is this information publicly accessible - lists of councils and the location covered? Is there a way of getting this from google maps API? Because Google must know this information, about county borders etc, but how do you actually show it on the map?

Or have twitter plotted these maps themselves?

Answer 1

I'm pretty sure that you can get them here. Unfortunately, I don't speak British, so there is a lot of jargon there that I don't understand.

Edit:

I'm pretty sure that the boundary data on this page has what you are looking for. There are many tools around for dealing with ESRI shapefiles.

Answer 2

MySociety keep an almost religious eye on boundary changes of councils, as well as the other overlapping but different regions such as counties, electoral areas, postal areas and so on.

Some (all?) of their projects are open source - I think you can get the data you require. One of the blog posts has details on recent changes to council boundaries and accessing their data here:

• April Fools’ Day Council changes

I'm sure the Ordinance Survey are just as accurate, but probably expensive.