Soaring above the old city, this magnificent building is graced with a tiled entrance portal (one of the tallest in Iran), flanked by two 48m-high minarets and adorned with inscriptions from the 15th century. The exquisite mosaics on the dome and mihrab, and the tiles above the main western entrance to the courtyard are masterpieces of calligraphy, evoking sacred names in infinitely complex patterns.

　　Built for Sayyed Roknaddin in the 15th century, the mosque is built on 12th-century foundations over a former fire temple and with access to the Zarch Qanat (a stairwell leads down to part of this ancient water channel but is closed to the public).

　　The Jameh Mosque is particularly notable for the prevalence of faience – a form of tiling that, like mosaic, is formed of different coloured pieces that are sandwiched together to create the design. These predate later uniform tiling, which feature painted designs. The gardoneh mehr (swastika symbol) used on some tiles symbolises infinity, timelessness, birth and death, and can be found on Iranian buildings dating back as early as 5000 BC.

　　This is one sight where having a guide (and ideally a rudimentary knowledge of Arabic script) can transform the experience of a visit as it is impossible to guess at the calligraphic conundrums involved in the design without expert interpretation.

　　The most revered object in the small museum, which is only open in the mornings, is a piece of hand-loomed cloth that once adorned the Kabbah in Mecca.