The Peninsula Ridge forms the drainage divide between the Gulf of Carpentaria and the Coral Sea. To the west, large, winding river systems including the Mitchell, Coleman, Holroyd, Archer, Watson, Wenlock, Ducie and Jardine flow into the Gulf of Carpentaria. During the Dry season, those rivers become a series of waterholes and sandy beds. Yet, with the heavy rains in the Wet season, they become mighty waterways, spreading across huge floodplains and coastal wetlands and giving life to many freshwater and wetland species.