Interactive map of London by language (other than English) most likely to be spoken at each Underground station http://tubecreature.com/#/tongues/current/same/*/*/TFTFTF/12.68/-0.1034/51.5263/ …pic.twitter.com/L1tbLD6GUe
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I think the data is from 2016. It would be interesting to see how much it changed since then.
I think it's going to be dramatic. When I first moved to London there were so many French speakers.
Oh, it seems they updated it since I last saw it? Nice! 
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