Closing the north side of Registan Square, the Tilla Kari Madrasa stands out from the vertical structures of its neighbours due to its broad façade covered in geometrical patterns; it is almost as if it were being squashed down by the imposing blue cupola of the mosque housed in its left wing. Inside, the cupola is entirely overlaid with gold leaf. The decoration is exceptionally fine, this mosque having been built to replace the Bibi-Khanym Mosque, which had already collapsed at the time.