Even locals can't decide on pronunciation - Shrewsbury is pronounced as it is written unless you're posh, when it becomes Shrowsbury.
https://www.shropshirestar.com/news/2015/06/27/shrowsbury-or...
https://www.shropshirestar.com/news/2015/06/27/shrowsbury-or...
https://en.wikipedia.org/wiki/Welsh_exonyms#United_Kingdom_(...
[*] - according to my made-up-on-the spot stats