Have you ever been asked the address of where you will be staying? Maybe a customs agent asked or you needed to list it on some official form before you get through customs.
If you are staying in one hotel or one vacation rental, keep that address somewhere you can access it easily. If you’re moving around from hotel to hotel or from city to city, at least keep the address of the first place where you will be handy.
Might as well start your trip off with no stress.