The Jameh Mosque, or Friday Mosque, was founded in 1349 by the Muzaffarid ruler Mubariz al-Din Mohammad, and although it has been rebuilt and embellished many times, the core layout of four iwans around a central courtyard is original. The eastern iwan is the highlight: an enormous arch of muqarnas — honeycomb vaulting — entirely covered in lapis-blue and turquoise tiles, framed by Kufic and Thuluth inscriptions in white and yellow.
The mosque is still in active worship use. Visitors are welcome outside prayer times; modest dress is expected (a chador is provided at the entrance for women if needed). The acoustic of the central courtyard is remarkable — voices carry from one iwan to another with startling clarity.