The Jameh Mosque of Isfahan (مسجد جامع اصفهان) is the grand, congregational mosque within 
Isfahan province and can be seen as a stunning illustration of the 
evolution of mosque architecture over twelve centuries. The Mosque is 
the result of continual construction, reconstruction, additions and 
renovations on the site from around 771 to the end of the 20th century. 
The origins of this Mosque lie in the 8th century although it is thought
 to be burnt to the ground leaving only some of the south and north 
prayer halls intact.  It was rebuilt in the 11th century and went 
through remodeling many times. As a result it has rooms built in 
different architectural styles and represents a condensed history of the
 Iranian Architecture. Spanning more than 20,000 square feet, it is one 
of the oldest mosques still standing in Iran, and it was built in the 
four-prayer hall architectural style, placing four gates face to face. 
Responding to functional needs of the space, political ambition, 
religious developments, and changes in taste, further additions and 
modifications took place incorporating elements from the Mongols, 
Muzzafarids, Timurids and Safavids. Of note is the elaborately carved 
stucco altar commissioned in 1310 by Mongol ruler Oljaytu, located in a 
side prayer hall built within the western arcade. Safavid intervention 
was largely decorative, with the addition of niche-like cells, glazed 
tilework, and minarets flanking the south prayer hall.  The harmony of 
the brickwork, the tile work added later, as well as the plaster 
moldings, inscriptions, and other decorations in a setting of glorious 
simplicity, engulf the beholder in an almost spiritual aura.
The Mosque has 8 entrances, each of them built in a different period and
 the oldest of them on its northeastern side now blocked.  Its current 
main entrance is located on its southeastern side.  All the buildings 
are set round a fine rectangular central courtyard leading to a prayer 
hall on each side of it.  The main courtyard spans 60 by 70 meters which
 contains two pools, one of them partially covered by a platform raised 
on top of four columns which in the past had been used as a lectern.
Construction under the Seljuqs included the addition of two brick domed 
chambers, for which the Mosque is renowned. Its double-shelled ribbed 
domes represent an architectural innovation that inspired builders 
throughout the region.  The south dome was built in 1086–87 and was 
larger than any dome known at its time. Inside the dome has been adored 
with Mongol-era stalactite mouldings and two minerats. The north dome 
was constructed a year later as a direct riposte to the earlier south 
dome, and successfully so, claiming its place as a masterpiece in 
Persian architecture for its structural clarity and geometric balance. 
Inside it is filled with massive cursive Quranic inscriptions.  Prayer 
halls were also added in stages under the Seljuqs, giving the Mosque its
 current four-prayer hall form, a type which subsequently became 
prevalent in Iran and Central Asia.  The prayer hall facing Mecca on the
 southern side of the Mosque was vaulted with niche-like cells during 
the 1300s.
The Mosque contains alabaster lighting systems for prayer rooms below 
ground along with a wooden carved minbar and is built on grounds that 
used to be a Zoroastrian Fire Temple.   In 2012 the Jameh Mosque in 
Isfahan was approved as a World Heritage site in the 36th session of the
 UNESCO World Heritage Committee.
