Where cities end and something else – suburbs, exurbs, countryside begins is a source of practically infinite disagreement. Is Sunderland a part of Newcastle? The Black Country an extension of Birmingham? The resulting arguments are great if you’re a cities-focused website with traffic targets to meet, but not so great I’d you’re trying to come up with a sensible devotion policy.

One way of settling the debate, of course, is to just ask people. So that’s what Alasdair Rae, a lecturer in the geography department of the University of Sheffield, has done. He’s created this mapping tool under the headline “Draw your city – go on, you know you want to”:

This is a little experiment to crowdsource information on the area you think different cities cover, in addition to a little information on how long you’ve lived there – if at all. Zoom in or out if you need to and then click ‘Start Mapping’ in the top left of the screen.

Sometimes official city boundaries extend far beyond the urban fabric, and sometimes they don’t include very much of it at all. I want to see what people consider to be part of their city, or not. All the drawn boundaries on this site come from your contributions.

It’s a work in progress – but you can already see some of the results. With London, the most popular boundary seems to be the M25 orbital motorway. That said, some seem to think London should either exclude most of the outer suburbs, or swallow large chunks of the south east. One brave soul even seems determined to stick to the ancient City of London:

In Glasgow, too, there’s a division between those who think only the inner city really counts, and those who’d include large chunks of the surrounding counties:

With Birmingham, no one seems sure what to do with Wolverhampton, Coventry or the rest of the West Midlands urban area:

Things are no clearer in the north of England – although so far there are more takers for defining Manchester or Sheffield than there are for tackling Liverpool or Leeds:

Others have been drawing boundaries internationally. Here are some proposed definitions of New York City and Philadelphia:

In Paris, the traditional city boundary is clearly more popular than the attempts to create the Metropole de Grand Paris:

It’s not clear everyone’s taking this entirely seriously, though:

(Rae deleted the offending boundary, but not before tweeting a screenshot.)

You can draw a line around the city of your choice on Rae’s website here. Go on. You know you want to. 

Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.

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