(i) One of the most important inland route for trade since ancient times.
(ii) A great source of irrigation which helps in the development of agriculture.
(iii) The alluvial soil along its bank is the most fertile soil to grow various commodities.
(iv) Due to the surplus production that it gives enables the other economic activities like setting up of manufacturing Industries and other related activities.
(v) Now a days it also acts as a major source of energy (i.e. hydroelectricity) which is the backbone of other economic activities.

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