In the upper reaches (to the village of Efremkino) of the Bely Iyus it is called Pikhterek and has the character of a fast mountain river, but not deep and in summer there are fords everywhere.

In the middle reaches it flows among the hilly steppe spaces of the western outskirts of the Chulym-Yenisei basin, strongly meandering channel, swampy valley.

There are more than 10 settlements in the valley: Berenzhak, Mendol, Malaya Syya, Efremkino, Bely Balakhchin, Iyus, Solenoozernoye, etc.

[6] The Iyussky Reserve [7] located on the eastern slope of the Kuznetsk Alatau, in the basin of the middle course of the Bely Iyus River, Shirinsky District, Khakassia.

The Iyussky Reserve has been established to protect cave complexes, biocenoses of the forest and subtaiga zone, habitats of ungulates, nesting sites of rare birds of prey, for organized cultural leisure of the population (ecological and tourist routes, visiting caves, etc.).

[1] In the vicinity of the village of Malaya Syya (Shirinsky district) on the banks of the White Iyus, there is the earliest settlement of Homo sapiens on the territory of Khakassia, the Paleolithic site of Malaya Syya (30-35 thousand years ago), where drilled jewelry processed with incisors was found Radlov Vasily Vasilievich (Friedrich Wilhelm Radloff) in his travel notes noted the statue that Daniel Gottlieb Messerschmidt found on the Ak-Iyus (Khakas: Ах-Ӱӱс ), which, in appearance, quite corresponds to the stone women (Russian: каменные бабы) of the southern Russian steppes.