The Danau Sentarum National Park is a national park protecting one of the world's most biodiverse lake systems, located in the heart of Borneo Island, Kapuas Hulu Regency, West Kalimantan Province, Indonesia. It lies in the upper Kapuas River tectonic basin some 700 kilometres upstream from the delta. The basin is a vast floodplain, consisting of about 20 seasonal lakes, freshwater swamp forest and peat swamp forest. Local people call it as Lebak lebung (floodplain). The National Park is located in the western part of this basin, where three-quarters of the seasonal lakes occur. Approximately half of the park consists of lakes, while the other half consists of freshwater swamp forest.