BR Diesels
North British Locomotives - Diesel Shunters and Mainline
Scottish Railways
Former Great Eastern Railway Lines
Post Steam era BR
Brush Locomotives including Bagnall Shunters
I’ve lived in Peterborough for thirty five years and worked for the Rivers Authority at one time, and until quite recently, I’d never heard the “nen” pronounciation at all.
Nowt to do with the Anglo-Saxons. It's of Celtic or pre-Celtic origin, so isn't pronounced with a middle dipthong as in English. Plus many locals pronounce it with a short or pure vowel sound as 'Nen', as do my maternal family from Wisbech - and rightly so!