It is located nearby Kaynar village on the right bank of the river Akhangaran, 10 km to the North from the settlement Akhangaran. Sardoba was described in 1934 by the academician M. E. Masson. Sardoba is built from a burnt brick in the form of a dome (cupola) over a spring, water source. According to the legend construction belongs to the first half of the XIX century.
It is located in 12 km. to the north-west from the village Karakhitay. It dates back to XIX century. The only remained monument of water supply engineering in the area. The karavansaray is in dilapidated condition.