The surroundings and wonderfull playgrounds, swimmingpool etc makes the visit  worth 

 PKL#2 Provinciedomein Kessel-Lo 

 PKL#4 Provinciedomein Kessel-Lo

If they are old enough to do a adventurous hike this is a good one

The solution to get to the cache is hard to find, but the technique is wonderfull.

The sudoku for the parents the nice cache for the kids

Nice walk in a beatifull park and instructive as well

If you like birdhouses this series is top!! Needs an adult to figure out the caches.

All the caches on this list are kid-friendly or my kids  loved them.