Flowing for over 42 kilometres through the greater Montreal region of Quebec, the Rivière des Mille Îles connects Lac des Deux-Montagnes and the Ottawa River to the St. Lawrence River, weaving through a landscape of islands, shallow bays, and lush aquatic vegetation. The river passes through communities including Terrebonne and Laval, forming the backbone of the Parc de la Rivière-des-Mille-Îles, a protected natural corridor that harbors an extraordinary diversity of wildlife. Remarkably, approximately 59% of all freshwater fish species found in Quebec can be encountered in this river, making it one of the most biologically rich waterways in the province. The river is characterized by shallow, weedy water with abundant aquatic grass beds and island archipelagos — ideal habitat for a wide range of warmwater species. The Mille Îles is also part of La Route Bleue, a 155-kilometre navigable route beginning on the Ottawa River and ending near Repentigny, underscoring its significance as a paddling and fishing corridor.