Sheikh Zaynuddin (also known as Zayniddin), the patron saint of Tashkent, was born in Baghdad in the 12th century and was founded to spread Sufi teachings in Tashkent. The sheikh prayed there, along with the chillakhana, an underground structure with a dome that has survived to this day.

During reconstruction, an archaeologist determined that the dome was built seven or eight years earlier. There are openings in the apex of the dome and in the floor of the upper tier, allowing a ray of sunlight to pass through the nix on the day of the summer solstice, which allowed for the precise calculation of the calendar needed for agricultural work.

Zaynuddin Baba, who, according to legend, lived for 95 years, is buried next to the chillakhana. A mausoleum was erected over his grave by order of Amir Temur.

The mausoleum is currently located in the middle of a large cemetery in Kukcha, where many pilgrims and tourists are euthanized and preserved in the cold house that once housed the old observatory.