Roughly in the middle of its course, the Araguaia river splits into two forks, with the western one retaining the name Araguaia and the eastern one being called Rio Javaés. They flow their separate ways for over 400 meandering kilometers before reuniting, thus forming the Ilha do Bananal, the world's largest river island. Where the Javaés pours back into the main Araguaia, it forms a broad inland delta where it pours back into the main Araguaia, a 100,000 hectare triangular expanse of igapó flooded forest, blackwater river channels, and oxbow lakes. This inland delta is called Cantão.