The oldest medrese on Registan, is a large rectangular building with monumental portal and a yard with four-verandahs, surrounded by cells for students and with four classrooms in the corners. In the western part is a winter mosque. The corners of the building are decorated with high minarets. The decorations consists of glazed and unglazed bricks, mosaics, majolica, carving marble. The most beautiful decorations are those of the main portal, where geometric, vegetative and epigraphic decorations were used. Inscriptions mention Ulugbek and several dates relating to the stages of construction. Construction of the medrasah finished in 823 (1420).