The Kosi River is a major river in northern India, primarily flowing through the state of Bihar. It is known for its unique braided river system, which consists of multiple channels that shift frequently due to sediment deposition. The river originates from the Himalayas in Nepal and travels approximately 229 kilometers before merging with the Ganges River. The Kosi River is often referred to as the "Sorrow of Bihar" due to its history of devastating floods that affect local communities. These floods are caused by the river's high sediment load and its tendency to change course. Efforts have been made to manage the river's flow and mitigate flood risks, but challenges remain for the residents living along its banks.