A veritable green setting near Souppes-sur-Loing, the Sensitive Departmental Natural Area of ​​the Marais de Cercanceaux is home to many animal and plant species. Fauna and flora feed on this humid environment of great interest. Built using a wooden pontoon, a walk of more than 5.5 km in the middle of nature allows you to discover the natural environments with the help of explanatory panels along the way. The different environments (the river, the ru, the ponds, the marsh, the pond and the wet meadow) attract unusual species such as the night heron, the water rail and the sculpin.