In Groenalliantie Midden-Holland the municipalities of Bodegraven-Reeuwijk, Gouda, Krimpen aan den IJssel, Krimpenerwaard, Waddinxveen and province Zuid-Holland work together on nature, landscape and open air recreation. Staatsbosbeheer manages the nature reserves and recreational areas in the Krimpenerwaard and the Reeuwijkse Plassen and surroundings.