The Agha Bozorg Mosque is one of the most architecturally accomplished religious buildings in Iran, constructed in the late 18th century by the master builder Ustad Haj Sa'ban-Ali. Unlike most Iranian mosques, it is built into the ground rather than above it — the main courtyard sits several metres below street level, creating an effect of extraordinary calm when you descend into it from the bustle of the bazaar nearby.
The complex combines a mosque and a madrasa (theological school) around a single sunken courtyard with a central pool. The geometry is precise and sober — the decoration here is restrained compared to the merchant houses, relying on the proportions of the arches and the play of light rather than surface ornament. Two slender minarets rise above the entrance portal.
The basement of the mosque contains the tomb of the cleric who commissioned it, and the madrasa rooms around the upper courtyard are still occasionally used for religious study. Early morning is the best time to visit, before tour groups arrive.
Hours: Open to non-Muslim visitors during non-prayer times; modest dress required