* Oka River: The Oka River is another major tributary of the Volga River in Russia. It is the second longest tributary in Europe, and it drains an area of about 245,000 square kilometers (95,000 square miles). The Oka River originates in the Central Russian Upland and flows into the Volga River near the city of Nizhny Novgorod.
* Vetluga River: The Vetluga River is a tributary of the Volga River in Russia. It originates in the Kirov Oblast and flows into the Volga River near the city of Kozmodemyansk.
* Sura River: The Sura River is a tributary of the Volga River in Russia. It originates in the Penza Oblast and flows into the Volga River near the city of Vasilsursk.
* Samara River: The Samara River is a tributary of the Volga River in Russia. It originates in the Orenburg Oblast and flows into the Volga River near the city of Samara.
* Sviyaga River: The Sviyaga River is a tributary of the Volga River in Russia. It originates in the Ulyanovsk Oblast and flows into the Volga River near the city of Ulyanovsk.