I always have one but each time I rented a car in Europe they never asked for it. Im sure the one time I don't have it. Thats when they will ask.
I have actually been harassed by law enforcement for not having one. I have been stopped twice for paperwork checks and the one as I mentioned gave me a hard time the 2nd time was told they don't recognize the IDP and that tourists should have a European License. Either way it is a valid ID document as well which in itself is worth it.
IDP has several different languages that explain the USA drivers license and that you don't have any infractions against it and lawfully you are able and capable of driving. Yes I have heard individuals say they are never asked but I rather be safe than sorry. Wayne Mineo it's really for the police officers in the country you are in to show that you are a legitament driver .
I asked about this early this year due to up coming travel. Just show your license, pay a small fee and you are done. To my understanding., it better to have the international over your state issued. Easier to work with while in Europe.
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