Andi Koysu River

The Andi Koysu (Andiyskoe Koysu) is a major transboundary river that begins its journey in the high-altitude, pristine region of Tusheti in northeastern Georgia. It is officially formed by the confluence of two significant mountain rivers: the Pirikita Alazani and the Tushetis Alazani. From this junction, the river flows northeast, crossing the border into the Republic of Dagestan in Russia, where it eventually merges with the Avar Koysu to form the Sulak River, which empties into the Caspian Sea. The total length of the Andi Koysu is about 144 kilometers, though only its very upper reaches are within Georgian territory. The river is renowned for its immense power and the spectacular, incredibly deep canyons it has carved through the Caucasus Mountains. The terrain it traverses is wild, rugged, and largely inaccessible, characterized by steep cliffs and alpine vegetation. The Andi Koysu basin is a haven for biodiversity and offers some of the most extreme and awe-inspiring landscapes in the entire Caucasus region, attracting experienced trekkers and nature enthusiasts to its remote Georgian headwaters.