Naqsh-e Jahan Square , known as Imam Square , is a square situated at the center of Isfahan city, Iran. Constructed between 1598 and 1629, it is now an important historical site, and one of UNESCO's World Heritage Sites. It is 160 meters wide by 508 meters long . The square is surrounded by buildings from the Safavid era. The Shah Mosque is situated on the south side of this square. On the west side is the Ali Qapu Palace. Sheikh Lotf Allah Mosque is situated on the eastern side of this square and at the northern side Keisaria gate opens into the Isfahan Grand Bazaar. Today, Namaaz-e Jom'eh (the Muslim Friday prayer) is held in the Shah Mosque.