Turgai is a river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 that sits in the Turgai Valley in Kazakhstan

Kazakhstan

Kazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...

.

It is 825 km long, the surface is 157,000 km². Average water consumption is around 9 cubic meters/second. The Turgai disappears in the sinkless hollow of Shalkarteniz.
It is composed of erosion-tectonic basin in northwestern Kazakhstan, between the Urals and Mugodzhar Hills

Mugodzhar Hills

Mugodzhar Hills is a series of mountain ranges in Northwestern Kazakhstan 275 miles long. Latitude : 48° 38' 38 N Longitude : 58° 32' 47 E...

 in the west and the Kazakh Steppes in the east. In the north - dry steppes (район освоения целинных и залежных земель), semi-steppes in the south. Deposits of iron ore and other minerals.

Turgai plateau crosses from south to north. The Thurgau Ubahan (tributary of the Tobol) along with all the rivers of in the Turgai valley has many lakes. This is where the Naurzumskyy reserve

Naurzum State Nature Reserve

Naurzum State Nature Reserve is a nature reserve in Kazakhstan. It is part of the UNESCO heritage site Saryarka — Steppe and Lakes of Northern Kazakhstan. It protects about 3077 sqkm of steppes, semi desert and forests.- Size :...

 is located which connects the West Siberian Plain in the northern part of Kazakhstan Turan lowland.

Length of about 630 to 800 km., Up from 20-75 to 300 km. The valley depth ranges from 125 to 300 m. deep.