ISNA | Mohammad Ghajar: �Torkaman Sahra Plain�, located in two provinces of Golestan and North Khorasan, is nearly 400 square kilometers in extent. The Plain has stretched from the coasts of the Caspian Sea in Bandar-e Torkaman City and Turkmenistan is located in north of it. Mud volcanos, mountain heights, valleys, constructed wetlands, natural dams, big and small hills, the ancient Atrak River, etc. all have created the fantastic scenery of this Plain. The region also boasts different historical sites such as Gonbad-e Q?bus Tower, which is an outstanding and technologically innovative example of Islamic architecture, the Great Wall of Gorgan, and the tomb of Khalid Nabi and its mysterious cemetery.