Many traces of man-made fortresses, buildings, different constructions have been preserved on the Turkmen land, as the signs of the hard work of our ancestors. There is much interesting information in historical written sources about some of them. Among these monuments, the most famous is Sultanbent, a special dam built on the banks across the Murgap River.
According to written sources left by travellers, Sultanbent has more than a thousand years of history. Speaking about the Murgap River, Al-Maqdisi, the Arab geographer, who lived in the 10th century, wrote that its water was stored in one place until it was full and then the water went towards Merv. The Arab geographer wrote that about ten thousand people worked under the Emir's supervision over the river protecting people from water floods. It can be assumed that the place where the Arab geographer claims that the water overflowing near that dam is an ancient form of the present water structure of Sultanbent. Pointing to the idea that there where the water overflowed was a specially restored dam, Maqdisi himself wrote: «The Murgap River is blocked by very beautiful wooden dams about 6-7 kilometres from Merv. To control the water level, measurements were made on the board with a dotted line in the middle of the river. When the level of the water rises to the sixtieth line, it gave hope that the year would be fruitful. The population was happy that river monitors would increase the share of the water. There were also indoor pools in Merv. Their water was distributed to the population in dry years. More than a thousand people worked on this huge water industry in Merv. The main dam had more than 400 water pipes, and if weeds accumulated in front of them in winter, observers entered water their bodies with mummies and cleaned the aqueducts».