It extends from the lower slopes of the Alborz and Kopet Dag mountain ranges to the steppes of Turkmenistan.
The River Gorgan flows through the plain from east to west, emptying into the Caspian Sea.
[1] The provincial capital Gorgan lies to the south of the plain, which covers an area of about 170 square kilometres (66 sq mi) and is situated between 37°00' and 37°30' north latitude, and between 54°00' and 54°30' east longitude.
[3] The sites are thought to relate to the Jeitun culture of southern Turkmenistan and may date to the sixth millennium BC, judging by the age of the artefacts found at Sang-i Chakmak.
It stretched for nearly 200 km (124 mi) and protected the fertile plain from encroachment by White Huns from the north.