[dacox]

I think a city level would be great, and interesting. Looking at national numbers misses a lot. For example, Canada and the USA are very similar.

However, I live in Vancouver, and when I went to Chicago last year, the tap water was unbelievably bad (tasting). Even the complimentary bottled water in my hotel was bad.

[smayr]

Indeed, just looking at the data on a country-level misses a lot! I am working on providing city-level data, which by the way is substantially harder as the data for most places is hidden deep on some government websites as a PDF, sometimes outdated, sometimes not available at all!