Greater Isfahan Metropolitan Area is a metropolitan region in
Isfahan Province, central
Iran. This region, although not having any official designation and recognition yet, is the second biggest one in Iran, behind the capital city
Tehran (
Greater Tehran). The overall region has a population of over 3,500,000 and extends along
Zayandeh Rud, the main river axis through the province, and also along the northern-southern axis of the city, plus a western axis towards
Lorestan Province. The region is a transportation hub and an industrial centre having concentrated all steel related industries in it. The region is also home to important military installations and centres, including nuclear facilities and airbases.