The Akhuryan or Arpachay is a river in the South Caucasus. It originates in Armenia and flows from Lake Arpi, along the closed border with Turkey, forming part of the geographic border between the two states, until it flows into the Aras as a left tributary near Bagaran. The Akhuryan is 186 km (116 mi) long, and has a 9,670 km2 (3,730 sq mi) drainage basin.