Unlike in other parts of the Caucasus region, the Gegham mountains have generated primarily small scale volcanoes.

Atis and Gtsain Ridge) from the Late Miocene has been dated at 5.7–4.6 Ma by K-Ar and is the oldest sequence in the region.

The volcanic activity peaked round 200 ka, when most of the Gegham centres formed from trachyandesitic lavas.

[1][2] The highest point is the volcano Azhdahak, elevation - 3597.3m above sea level, in the western part of the range.

Most images depict men in scenes of hunting and fighting, and astronomical bodies and phenomena: the Sun, the Moon, constellations, the stellar sky, lightning, etc.