Iskanderkul is a glacial lake located in the Fann Mountains of north-western Tajikistan,

within the Sughd Region. Positioned at an altitude of approximately 2,195 metres above sea level, the lake lies at the junction of three major mountain ranges: the Hissar, Zeravshan, and Fann. It occupies a tectonic basin and has a surface area of around 3.4 square kilometres, with a maximum depth estimated at 72 metres.
The lake is primarily fed by the Iskanderdarya River, which originates from surrounding glaciers and snowfields. Water exits the lake through the same river, eventually contributing to the Yaghnob and later the Zeravshan river systems. Seasonal variations in glacial melt significantly affect the lake’s water levels, especially during spring and early summer.
Iskanderkul is known for its distinct triangular shape and turquoise-blue waters, a result of mineral-rich glacial runoff. The surrounding terrain includes steep mountain slopes, scree fields, and alpine meadows. Just downstream from the lake is the 38-metre Iskanderkul Waterfall, also known as the “Fan Niagara,” which is a notable hydrological feature of the area.
The lake is situated within the Iskanderkul Nature Reserve, which spans over 300 square kilometres and is recognised for its biodiversity. The reserve is home to numerous bird species, including the Himalayan snowcock and bearded vulture, as well as mammals such as the Central Asian lynx and ibex. The combination of alpine ecosystems, hydrological importance, and geological context makes Iskanderkul a significant natural landmark in Central Asia.