Rivers of India · Ends in Ganga

Kosi River: source, course, dams and places

Q: Where does the Kosi originate?

At Formed in Nepal by the Sun Kosi, Arun and Tamur (Headwaters in Tibet and the Everest region).

Q: Where does the Kosi end?

In Ganga (Near Kursela, Katihar district, Bihar).

Kosi (Sapta Koshi · 'Sorrow of Bihar') is about 729 km long (total length). It rises at Formed in Nepal by the Sun Kosi, Arun and Tamur and ends in Ganga. A map-first summary for exam revision.

By Pradyumna Gayake · Updated 5 Nov 2026 · From the same data as the app’s Kosi study card

The Kosi drawn from AtlasMitra’s river data. Circle: source. Diamonds: dams and barrages. Dots: places on its course. India’s boundary as per the Survey of India.

Source

The Kosi rises at Formed in Nepal by the Sun Kosi, Arun and Tamur, Headwaters in Tibet and the Everest region. 28.55° N, 85.75° E

Course

Its main course runs Tibet → Nepal → Bihar, and it ends in Ganga: near Kursela, Katihar district, Bihar.

Key facts

Called the 'Sorrow of Bihar'
Known for shifting its course across a huge alluvial fan.

Dams and barrages

Dam	Where and what
Koshi Barrage	Bhimnagar, India–Nepal border.

Places along the Kosi

Place	Note
Supaul	Bihar · Kosi embankment district.

Quick questions

Where does the Kosi originate?

At Formed in Nepal by the Sun Kosi, Arun and Tamur (Headwaters in Tibet and the Everest region).

Where does the Kosi end?

In Ganga (Near Kursela, Katihar district, Bihar).

How long is the Kosi?

About 729 km (total length).

Which dams are on the Kosi?

Koshi Barrage: Bhimnagar, India–Nepal border.