Looking for fairly undiscovered areas of Belgium

Hey everyone, I'm moving to Belgium in a couple of months and I'm curious of authentic places and things to do. I've lived in Belgium in the past for 8 months and did most of the popular things and saw most of the touristic places already.

Now that I'm going to move in for good this time, I want to get familiar with and discover the most authentic places and things this time. This will not only give me new and better experiences but also help me to merge with the Dutch culture. Any kind of advice is appreciated!