Fondry des Chiens, a natural sinkhole in the Ardennes, is one of the most stunning and unique viewpoints that Belgium has to offer. And while you can reach it very easily by car, the better way to experience it is to follow a hiking trail that starts in the charming village of Nismes. There, you can park your car for free at the Moulin de Nismes and start following the route that is marked with a red-white-red flag. This 9-kilometer trail leads you along a the Viroin river, a dense forest, a beautiful railroad and so much more. Towards the end you will spot the 'Fondry des Chiens' signs, where you have to make a small detour to be rewarded with this amazing panorama, which some even call the Grand Canyon of Belgium.