Western Khorisar (elevation 3736 m) and Didi-Nepiskalo (3694 m) are the highest summits close to the crest of the Greater Caucasus. In the northeastern part of the system are the Nepiskalo volcanoes and several smaller structures. The Patara-Nepiskalo volcano is strongly degraded by glacial action and may have had a caldera. Other volcanoes are Sharkhokh, Northern Shadilkhokh, and Southern Shadilkhokh in the western Kaidon range and the lava flows created by the latter two volcanoes between the Arkhi Range, Keli Lake and the Aragvistavi river, the Ermani-Akhubata lava plateau, Eastern Sharkhokh volcano and several lava domes (Ermani, Fidarkokh and others).