After originating from the northern slopes of the Kailash range (Tibet), Indus flows north-westwards through Tibet and Ladakh. The River follows a long and nearly straight course in Ladakh, running between Ladakh Range and Zaskar Range.
The Shyok and Gilgit are its important right bank tributaries and the Zaskar is left bank tributary.
After crossing Himalayas through a very deep gorge, it turns to the south-west and enters Pakistan. It leaves the mountains at Attock and flows roughly southwards until it falls into Arabian Sea near Karachi.
It has a length of 2900 km from its source to the Arabian sea.