The mountain range Sunduki is a natural and historical monument of local significance in the Ordzhonikidzevsky and Shirinsky districts of the Republic of Khakassia, Russia.

It is the foothills continuation of the Efremkinsky ridge of the spurs of the Kuznetsk Alatau in the valley of the Bely Iyus river.

The status of protected areas was determined by the decision of the Khakass regional executive committee dated July 21, 1988 No.

[5] Under protection are: various variants of phytocenoses, preserved virgin areas of the steppes, habitats of valuable, rare and endemic plants (Bupleúrum scorzonerifólium (lat.

Sve on mountain Tағ Onlo (1st Sunduk) is a small fortified area on several rocky ridges separated by deep logs.

Sve on mountain Onlo is, apparently, part of the system of defensive structures in the valley of the Bely Iyus river.

[11] Today, the ruins of such ancient structures bear little resemblance to fortress walls and can be confused with the natural collapse of stones.

Due to the poor study and the almost complete absence of dating finds, until recently, many scientists considered such structures to be medieval Kyrgyz or Mongolian fortresses-shelters, in which people temporarily took refuge from attacks, even calling them "ancient Tatar mountain fortresses".

It is also possible that during the period of the Kyrgyz state (VI-XIII centuries), the ancient wall was restored or even partially rebuilt, which was reflected in folk tales.

Interesting to notice that heroic epic tales of the Yakuts called Olonkho, which resembles similarity with name of Onlo (1st Sunduk).

Khoho-Babay is said to have lived there, guarding the sacred valley from uninvited guests for thousands of years, and hiding its riches in a giant forged chest (1st Sunduk).

Interesting to notice description of the typical performances example of Yakut Shaman in action:[15] "During difficult and dangerous journey every shaman has places of rest, called Ouokh (Olokh), when he takes a seat during the dance, this signifies that he has come to an Ouokh; when he rises, he is ascending further up into the sky; if he falls down, he is descending under the earth.

5 Onlo chests are made of white stone (quartz or marble) and stand in areas where there is no outlet for these rocks nearby.

These petroglyphs are a kind of the Tagar heroic epic,[17] they show not only the difficult earthly path of the hero, but also the other world where he ends up after being killed by an enemy lurking in ambush, depicted in the lower part of the stone slab.

[20] He was the author of numerous scientific and popular science books, in particular on archaeoastronomy: interpretations of cultural monuments of ancient people.