The shallow lake near Unterlunkhofen AG is a very slow-flowing, dammed section of the Reuss south of Bremgarten. Its waters and banks, mud banks and gravel islands provide habitats for numerous plant and animal species at all times of the year. For many species of waterfowl and waders, the shallow lake is of great importance as a resting place during migration and as a wintering place.
There are observation points and information boards for the visitor.
