Estimated number of islands that form a vast and extraordinary network along the 891 km course of Brahmaputra through the state of Assam. More than 2.5 million people live on some of these islands in Assam- chars or saporisas - as they are locally called. They are found along the river from the states northern border with Arunachal Pradesh to the south west where the Brahmaputra enters Bangladesh. They represent a significant reality, comprising 8 percent of the total population of the state of 30 million.