Darya e Sindh or Sindh river

Longest River Of Pakistan is the Indus river which is about 1976 miles (3180 km) long. Originating in the Tibetan plateau in the vicinity of Lake Mansarovar in Tibet Autonomous Region, the river runs a course through the Ladakh district of Jammu and Kashmir and then enters Northern Areas (Gilgit-Baltistan), flowing through the North in a southerly direction along the entire length of the country, to merge into the Arabian Sea near port city of Karachi in Sindh. It is the major source of irrigation for the fertile agricultural lands of Pakistan. It is also called “Darya-e-Sindh” in Pakistan.  The river’s estimated annual flow stands at around 207 cubic kilometers, making it the twenty-first largest river in the world in terms of annual flow.