A delta is a large deposit of sand and soil at the mouth of a river formed from sediment carried downstream by the river water.
The name comes from the Greek letter D, which is called delta and is shaped like a triangle, because most of the world’s deltas are in the shape of a triangle.
The delta of the Nile River in Egypt is perhaps the world’s most well-known delta. But the largest delta on earth is in Bangladesh and eastern India.
This delta is formed by two rivers, the Ganges and the Brahmaputra The Ganges flows about 1,550 miles across India, and the Brahmaputra flows 1,700 miles from Tibet. The two rivers join in Bangladesh and empty into the Bay of Bengal.
The delta formed at the mouth of these two rivers covers about 30,000 square miles, an area more than half the size of the entire nation of Bangladesh!