The other day I came across a wonderful Wikipedia page entitled “List of places in England with counterintuitive pronunciations“. There are so many examples that the list is divided up across two different pages, A-L and M-Z. Unfortunately, the actual pronunciations are given in the International Pronunciation Alphabet, which I can’t read, so I went looking for a more accessible guide and found this one from BBC America. My favorite examples: Woolfardisworthy, which is pronounced woolsery (note that there are literally more silent letters than pronounced ones in the written name), Towcester, pronounced toaster, and Oswaldtwistle, pronounced ozzletwizzle (which is not too counterintuitive, but is a delightful word).
In the spirit of fairness, here’s the list of places in the U.S. with counterintuitive pronunciations. Early on the list is my hometown, Amherst, which is pronounced amerst, with a silent H. Not as bad as a silent “fardisworth”, but I still managed to mispronounce it for the first seven years that I lived here.