A water reservoir or water storage is a building that functioned as a water supply for home use.

To provide water for home use in the past, people made water reservoirs. They were built in private and public places, in caravansarais, center of cities and madrasa (religious school).

Water reservoirs are below the ground level for two reasons: to easily conduct surface water inside from the roof and to prevent the destruction of walls by water pressure.

The water reservoirs were all round in shape with a dome as a roof on top surrounded by some wind catchers which conducted air into the water reservoir to make the water cool by circulating inside. So, the dome also helped the heat leave the water reservoir.

Once a year, the skilled men entered the water reservoir through a hole form the dome for cleaning and preparing it to be filled with water. People were happy to have access to potable clean water during the whole year!

Shahdad city water reservoir is very large. It has a diameter of 13 meters and a height of over 25 meters.

People had to walk down many stairs to reach the water tap. there were two platforms at the sides of the water tap for rest.

Visiting the water reservoir is part of Shahdad tour.