These little lakes are the result of peat extraction from the 12th century to the interwar years.
This 40 hectare nature area in a meander of the river Avre at Moreuil has been the subject of a Biotope Protection order since July 16th 1991 and has been classed as a SIC/pSIC (site of community importance) within the European Natura 2000 framework.
As you walk around you'll come across a number of explanatory panels provided by Picardy Nature Conservancy. Génonville marshes, also known as "La Grande Anse marshes" have remained untamed and unspoilt. They are home to a number of different habitats and several plant and animal species of high environmental value. You can walk around these marshes on a discovery trail, passing from islet to islet over little wooden bridges.