A large river, 514 kilometers long, its basin is entirely located on the territory of Khakassia. The head of the river is located among the ridges of the Western Sayan, while its estuary lies where it meets the Yenisei near the city of Abakan. In the upper reaches, the Abakan is a typical mountain river with a narrow channel, blockages and rifts. Nearby the aal of Ust-Sos, the Abakan enters the expanse of the steppe, breaking into many branches and channels, and reduces the speed of the current.
The river is fed mainly by snow and rain, due to the large reserves of snow or showers in the mountains, there are frequent floods with the peak period in May-June, when the water flow can reach 1000 cubic meters per second, with an average long-term flow of 300 cubic meters, and a minimum of 30 cubic meters.
The largest tributaries of the Abakan are the Ona, the Dzhebash, the Tashtyp, the Askiz, the Uibat. In the upper reaches of the Abakan River, there is a radon source called Goryachiy Klyuch, which is a popular wild resort, and also the lands of protected areas. The river is rich in fish, and its banks are rich in taiga, especially in the upper reaches. In the first half of the 20th century, timber was rafted along the Abakan for the construction of settlements and infrastructure facilities. 4 road bridges and 2 railway bridges were built across the river. The Abakan River is of great importance in the culture and traditional way of life of the indigenous population.