A river enters the sea or disappears before joining the sea is called its _________.
The last past of the river when it reaches the end of its journey, it is called an old river or the old stage. The end of the river is called the mouth. At the mouth, there is often a river delta, a large, silty area where the river splits into many different slow-flowing channels that have muddy banks. At this stage deposition is the only work of the river.