This sanctuary is an aquatic reserve with approximately 4.877 hectares at the end of the "Rio Cruces" (Crosses River), in the province of Valdivia.
In 1981 this sanctuary was put under the category of a `nature sanctuary´, and in the same year was put on the roster of the Internationally Important Wetlands (Ramsar Convention), making it the first piece of land in Chile to be included in this plan to protect wetland areas, especially aquatic habitats.
The "Carlos Anwandter" Nature Sanctuary at Rio Cruces was begun as a consequence of the earthquake and seaquake in 1960 when the land sunk in and the agricultural lands were flooded along the banks of the río Cruces and Chorocamallo River. Here there appeared leafy aquatic plants
surrounded
by small evergreen forests where an infinite number of both native and exotic birds nest. Among these birds we can find the Black necked Swans, African Herons, White-necked Herons, Terns, White-Faced Ibis, and Coots, and also the mammals such as the Coypou and the Nutria in the river.
The sanctuary has transformed into a source of pride and a symbol of natural beauty for the habitants of Valdivia.