Belgium
For an original city experience rent bicycles for the day ( 13 euro for the day) and cycle through the spectacular forest de soignes (10-15 km) and have a picnic on the grounds of the chateau de la hulpe.
If you dont feel like carrying your own food, there is a lovely restaurant cafe on the ground and a museum ( fondation folon) to add a little culture to the day out of the city in the city.