Chatkal Range is a range in the Western Tian Shan that borders Ferghana Valley from northwest. It departs from Talas range and spreads out to south-west to the right bank of Angren (river). The length of the range is 225 km, and it is up to 30 km wide. The highest elevations of the Chatkal Range are located in its north-east part. The ridge is crowned by pointed peaks with elevations of 4300 to 4500 m with Avletim peak - 4503 m being the highest point. Between peaks are saddles and mountain passes: Avletim - 3447 m, Shaar - 3809 m, Semiz-Bel - 3570 m, Chanach - 3401 m, Tush-Atu - 3595 m, Chapchyma - 2841 m, and Chaykyldy - 3264 m. Northern slopes are steep and short, while southern ones are gentle. The range is composed by primarily of limestone, granite, and schist. The axial line of the range is composed of limestone of Lower Carboniferous and Upper Devonian.