The Psou (; ady, Псыу; ka, ფსოუ; ab, Ҧсоу; russian: Псоу) is a river in the

West Caucasus The Western Caucasus is a western region of the Caucasus in Southern Russia, extending from the Black Sea to Mount Elbrus. World Heritage Site The Western Caucasus includes a natural UNESCO World Heritage Site comprising the extreme west ...

, bordering the

Gagra Range Gagra Range (; ka, გაგრის ქედი, tr; russian: Гагрский хребет, Gagrskij hrebet) is a mountain range of the Greater Caucasus in Abkhazia, Georgia.The range runs between the valleys of the Bzyb and Psou rivers to ...

to the east. It flows along the southern slopes of the

Greater Caucasus The Greater Caucasus ( az, Böyük Qafqaz, Бөјүк Гафгаз, بيوک قافقاز; ka, დიდი კავკასიონი, ''Didi K’avk’asioni''; russian: Большой Кавказ, ''Bolshoy Kavkaz'', sometimes translat ...

Mountain Range and forms a part of the border between

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

(

Abkhazia Abkhazia, ka, აფხაზეთი, tr, , xmf, აბჟუა, abzhua, or ( or ), officially the Republic of Abkhazia, is a partially recognised state in the South Caucasus, recognised by most countries as part of Georgia, which ...

) and

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-ei ...

. Its source in the Aigra Mountain, and it flows into the

Black Sea The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Rom ...

. The Psou is long, and the

drainage basin A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, ...

is approximately . Between the mouth of the river and the mouth of the Mzymta is a "sandy depositional foreland", which is approximately in length and wide. The principal tributaries of the Psou are the Besh and the Pkhista. Between 1913 and 1955 there was a hydrological station in operation at Leselidze, roughly upstream of the river mouth. The Psou gained notoriety as a smuggling route out of the country, by-passing Russian controls on the border. As of 2008 it was still designated as a transboundary river which lacked an international cooperation agreement as part of the UNECE Water Convention.

References

{{Rivers of Georgia Rivers of Krasnodar Krai Rivers of Georgia (country) Rivers of Abkhazia International rivers of Europe International rivers of Asia Georgia (country)–Russia border Smuggling routes Drainage basins of the Black Sea