We are visiting Crikvenica where my wife's grandfather was from. We would like to find out more about his family etc. How would we go about this?
You could start with the local Council (Općina) and the church in which he may have been baptised. If you have the correct spelling surname, that could be a good start. There are likely to be living relatives in Crikvenica that might know about the grandfather.
Do you have any idea where their house stood and to which parish they belonged?
At that age the registrar was the local priest, not in the municipality