Hyatt credit cards offer 2 free nights after meeting a minimum spend. They are changing the rules for applying for Chase cards (Hyatt is one) soon, so you might want to read up on that and apply shortly.

That being said, as Yoshi212 says, Europe is a big place. Hyatt has really poor coverage, so it might not make sense for you to get Hyatt nights if where you want to go has no Hyatt.