Hanhowuz, also known as Khauz-Khan is a reservoir in Mary Province

Mary Province

Mary Province is one of the welayatlar of Turkmenistan. It is in the south-east of the country, bordering Afghanistan. Its capital is the city of Mary. Its area is and population 1,480,400...

 of southeastern Turkmenistan

Turkmenistan

Turkmenistan , formerly also known as Turkmenia is one of the Turkic states in Central Asia. Until 1991, it was a constituent republic of the Soviet Union, the Turkmen Soviet Socialist Republic . Turkmenistan is one of the six independent Turkic states...

. It is located at 37°13′56"N 61°14′37"E. The M37 highway passes nearby and the village of Hanhowuz stands on the northwestern shore, with the city of Tejen

Tejen

Tejen is an oasis city in the Karakum Desert, in Ahal Province of Turkmenistan. It is located at latitude 37.3786 North; longitude 60.4961 East at an altitude of 161 meters...

 not too far away in that direction.

Hanhowuz Reservoir is a component of the Kara Kum Canal system and it was created to attempt to control the erratic Tejen River. It plays an important role in agriculture in the region. The reservoir was named after Oguz Han.