Friday Mosque of Shamakhi, 8th century mosque in Shamakhi, Azerbaijan.

The Friday Mosque of Shamakhi is a mosque in Shamakhi, Azerbaijan, with three prayer halls and a central dome. Its 1909 redesign by Józef Plośko added two flanking minarets, though a central cupola, side galleries and portal were cut for lack of funds. The only surviving sketch of the older building was drawn in 1847 by Grigory Gagarin.

The mosque was built in 743–744 CE, during the rule of the Arab commander Maslama ibn Abd al-Malik, brother of Caliph al-Walid I, who made Shamakhi his residence. It is the oldest mosque in the Caucasus after the Juma Mosque of Derbent, built in 734. The date comes from a 126 AH inscription on the façade, read by a geological commission from Tiflis led by Prince Shahgulu Qajar after the 1902 earthquake.

The mosque displays the Shirvan-Absheron architectural style that developed in this region and shaped religious buildings throughout medieval Caucasia. Visitors walking through the space can see how local building methods influenced the structural choices made here.

Check before entering whether prayers are underway, as the mosque may have limited access during those times. Guided tours explain the architectural and historical aspects to help visitors understand the construction methods better.

The 1902 earthquake destroyed most of Shamakhi and badly damaged the mosque; the rebuild was funded by donations through a special committee. Architect Zivar bay Ahmadbayov was dismissed after insisting the exterior be kept, and Józef Plośko's 1909 project added paired minarets and a central dome, though lack of money cut the dome, galleries and portal from the executed work.