The Korkodon is the fifth longest tributary of the Kolyma and the third in basin area. It has its sources in the
Korkodon Range of the
Kolyma Mountains. It heads first roughly northwards within a swampy valley between the Korkodon Range to the west and the
Molkaty and
Kongin ranges to the east. Halfway through its course it bends and flows west and then southwestwards, fringing the
Yukaghir Highlands. In its lower course it meanders and flows through a wide flat valley. Finally the river joins the right bank of the
Kolyma from its mouth at an elevation of . The Korkodon has some very long tributaries. The most important ones are the long
Bulun and the long
Bolshoy Yarkodon from the right; and the long
Pungali and the long
Biliriken from the left. There are over 1,100 lakes in the Korkodon basin, most of them of the
thermokarst type (
alas), as well as
swamps. The river freezes between mid October and mid May, but
polynyas may form in the lower reaches. ==Fauna==