The Shah Mosque is situated in the historical part of central Isfahan in Iran. The mosque is part of the “Imam Square”, one of the largest squares in the world. Construction of the mosque was already started in 1590, but it was mainly completed during the period 1630 to 1638. The mosque, which is also known as the Imam Mosque, is a masterpiece of Islamic architecture. It is rich in mosaics on its gateways, prayer halls and minarets. Both the slim, 50 m tall minarets resemble the 26 m tall entrance towers. The sky-blue onion dome is particularly impressive.