I'd imagine you'd want to do something you both would like to do and tells something about yourself. So what do you like to do that is girl and date friendly? Do you have some hobby or pasttime that is useable? Can also be a former hobby. One could also visit something you like or go watch something. Though personally I don't like to the latter, especially in the beginning. It allows for almost no interaction and conversation and is the ideal date for when you don't anything to say to each other any more. But that's hopefully months or years away.

Suggestions:
paintballing
water skiing
amusement park
I've seen ads of some musical event in Ghent, perhaps that's a possibility?
A day to Brugges or something similar?
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