Kok Gumbaz mosque is the main monument of Dar – ut – tilavat complex. It was erected by order of Ulugbek Kuragan in 839/1435. In the plan it’s square (12, 52×12, 61m), blocked by a dome, keeping on the sails. On the four sides there are the deep niches 4, 48 – 4, 63 m width. Epigraphic inscriptions are on the cylinder of the outer dome, laid out in mosaic, and also on the main façade and the interior of the building.
Different types of Arabic scripts along with traditional ornaments give the building splendor. The inscriptions on the portal are excerpts from the Koran (2:127 – 128). On the mosque cylinder there are Kufic inscriptions, made out of bricks. 1-2 verses of sura al-Fath (48) written in Kufic script with white letters on the yellow background. In the interior of the mosque there is a composition of the repeated sacred words. It’s written in yellow letters on the blue background with Kufic script banno: “Power belongs to Allah”. On the cylinder of the mosque there are inscriptions in Sulsi script with white letters on the blue background, of sura al-Jum’ah (62).