I've documented my travels around Manchester in search of mild here.

An oddity of the Manchester scene is that all the local brewers offer at least one mild, but most of them have stopped using the word 'mild'. So if you do get up here, look out for (dark milds) Holt's Mild, Robinson's 1892 Dark, Hyde's Owd Oak, Lees' Brewer's Dark, Thwaites*' Nutty Black and Timothy Taylor**'s Dark Mild, and (light milds) Robinson's 1892, Hyde's 1863 and Timothy Taylor**'s Golden Best. Six brewers, nine beers, and only two of them with 'mild' in the name.

*Not really a local brewery, but not far away.
**Not a local brewery at all, but you do see their beer around town and it's generally good stuff.