Beginning at 37°59′28″N 55°16′29″E / 37.99111°N 55.27472°E / 37.99111; 55.27472, where its tributary the Sumbar joins it, the river forms the border of Iran with Turkmenistan; this helped keep the area closed throughout the Cold War years.

A 1957 treaty between Iran and the USSR assigns equal rights to 50% of the water of the frontier parts of the Atrek.

Even though sturgeons concentrate in the area of the Caspian Sea next to the Turkmen coast, they do not currently migrate into the Atrek River owing to its low water level and pollution.

Since the Atrek is the only Caspian watershed river of the Turkmen coast, sturgeons no longer reproduce in Turkmenistan.

[3] This article includes content derived from the Great Soviet Encyclopedia, 1969–1978, which is partially in the public domain.