The Olyokma River is a tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Lena

Lena River

The Lena is the easternmost of the three great Siberian rivers that flow into the Arctic Ocean . It is the 11th longest river in the world and has the 9th largest watershed...

 in eastern Siberia

Siberia

Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...

. To the west is the Vitim River

Vitim River

Vitim River is a major tributary of the Lena River. With its source east of Lake Baikal, the Vitim flows 1,978 km north through the Transbaykalian Mountains and the town of Bodaybo. The river peaks in June and freezes from November to May. It is navigable from the Lena to Bodaybo. Upstream,...

, to the south the Shilka River

Shilka River

Shilka is a river in Zabaykalsky Krai, south-eastern Russia. It has a length . It originates as a confluence of the Onon and Ingoda rivers. Its confluence with the Ergune on the Russia-China border gives rise to the Amur River. The river is navigable for its entire length....

 and Amur River and to the east, the upper Aldan River

Aldan River

The Aldan River is the second-longest tributary of the Lena River in the Sakha Republic in eastern Siberia. The river is 2,273 km long, of which around 1,600 km is navigable. It was part of the River Route to Okhotsk...

. Its right branch, the Tungur (:fr:Toungir) River, leads to a portage to the Shilka. Yerofey Khabarov

Yerofey Khabarov

Yerofey Pavlovich Khabarov or Svyatitsky Erofej Pavlovič Chabarov , was a Russian entrepreneur and adventurer, best known for his exploring the Amur river region and his attempts to colonize the area for Russia...

 used this route to travel from the Lena to the Amur. Other tributaries are the Nyukzha River (:fr:Nioukja) and the Chara River (:fr:Tchara).

The river is approximately 820 miles (1,320 km) long. The Olyokma rises in the south of the Yablonovy Mountains, west of Mogocha

Mogocha

Mogocha is a town and the administrative center of Mogochinsky District of Zabaykalsky Krai, Russia, located at the confluence of the Mogocha and Amazar Rivers northeast of Chita. Population: -History:...

. It flows north through remote terrain before joining the Lena near Olyokminsk

Olyokminsk

Olyokminsk is a town and the administrative center of Olyokminsky District of the Sakha Republic, Russia, located on the left bank of the Lena River, southwest of Yakutsk. Population: -History:...

.