The Maribo Lakes have extremely high priority as a natural habitat. The lakes with meadows and woods are protected landscapes. The original preservation plan is from 1954 with certain additions and adjustments in 1957. A particular aim of the plan was to preserve the beautiful open vistas.
It is the only freshwater area in eastern Denmark which is covered by the Ramsar convention. This is an international convention for the protection of wetlands. Most of the other 26 Ramsar areas in Denmark are near the coasts or are marine areas.
Later the Maribo Lakes were chosen as EU-protected areas for birds, and in 2000 were proclaimed a nature reserve with specific regulations concerning traffic, sailing and hunting.