The largest freshwater lake in Southeast Asia, the Tonle Sap hosts an exceptional degree of biodiversity, earning it a prestigious UNESCO Biosphere Reserve status in 1997. Tonle Sap has a population of three million dwelling on its banks, of which approximately 90% are engaged in fishing and agriculture to support their living. This freshwater lake is home to a plethora of marine species, most notably the near-extinct Siamese crocodile and the legendary Mekong Giant Catfish, that is regarded as the largest freshwater fish in the world. Over 100 bird species, such as storks, pelicans, the threatened Bengal Florican, Oriental darter and the grey-headed fish eagle, call Tonle Sap home, making it a paradise for birdwatchers. Visit during the flood season, when Tonle Sap becomes the largest freshwater lake in Asia and sail past the colorful floating markets, testing your bargaining skills with the happy locals selling everything from fresh produce to local artefacts.