Aras (river)

The Aras is a major transboundary river located in the Caucasus region. A transboundary river is a waterway that flows through more than one country. This river is one of the longest in the Caucasus area. It serves as a vital geographic feature for several nations. It drains the southern side of the Lesser Caucasus Mountains. Meanwhile, the Kura river drains the northern side of those same mountains. The Aras eventually flows into the Kura river as a right tributary.

The river begins its journey in eastern Turkey. It is supported by the Kocagün, Dallı, and Orman streams. These streams originate from the Bingöl Mountains. They merge near the village of Tekman in the Kırıkhan district. After this, the Aras follows a complex path through many borders. It runs along the boundary between Turkey and Armenia. It also marks the border between Turkey and the Nakhchivan exclave of Azerbaijan. Later, it flows between Iran and both Azerbaijan and Armenia.

Many large tributaries feed the Aras, adding more water to its flow. The Akhuryan River, also called the Arpa Çayı, is a major source. This river gathers water from the Kars River and Lake Çıldır in Turkey. The Hrazdan River is another important tributary. It empties into Lake Sevan in Armenia before joining the Aras. Additionally, the Qareh Sū originates from the Sabalān Mountains in northeastern Iranian Azerbaijan. These various streams and rivers create a massive watershed.

History and ancient names reveal how important this river has always been. The Greeks called the river the Araxes in classical antiquity. Armenian tradition says the name comes from Arast, a descendant of the patriarch Haik. The name Araxes was also used for the Kura–Araxes culture. This was a group of prehistoric people living in these valleys. Even the Roman poet Virgil mentioned the river in his work, the Aeneid. Some ancient legends suggest the river once formed a massive lake without an outflow.

In modern history, the Aras became a significant political boundary. During the 19th century, treaties changed the borders of the region. The Treaty of Gulistan and the Treaty of Turkmenchay used the river as a limit. It marked the border between the Russian Empire and Qajar Iran. Because of these shifts, some people use the river to mark the line between Europe and Asia. This is a scheme that is not widely accepted by everyone. However, it shows how much the river defines the geography of the continent.

Humans have also modified the river by building large dams. These structures create reservoirs, which are large lakes used to hold water. Between 1963 and 1970, Iran and the Soviet Union built the Aras Dam. This created the Aras Reservoir near the city of Nakhchivan. Later, Iran built the Khoda Afarin Dam near the historic Khudafarin Bridges. This created the Khoda Afarin Reservoir. Iran also built the Giz Galasi Dam, which created the Giz Galasi Reservoir.

The Aras Valley is also a critical site for biological diversity. In 2006, a bird research center opened in the valley in Turkey. This center is located in the Tuzluca district of Iğdır Province. Between 2006 and 2021, researchers ringed more than 145,000 birds. They observed 306 different bird species at this location. This wetland holds 63 percent of all bird species found in Turkey. In 2012 alone, scientists found seven new bird species in the area. This includes the Shikra, which is a type of raptor.