The New Mosque, also known as Valide Sultan Mosque, is an Ottoman imperial mosque, which was constructed by the orders of Sultana Safiye, who was the wife of Sultan Murad III and later Valide Sultan (Queen Mother) of Sultan Mehmed III. It was built in the Eminönü neighbourhood, nearby Golden Horn, at the southern side of the Galata Bridge, and this location has made the mosque one of the most famous landmarks of Istanbul. The mosque is known as Istanbul’s last large mosque built by the Ottoman family. The construction of the mosque took more than half a century, making it the mosque with the longest construction period in the history of the Ottoman Empire. Davut Agha, an apprentice of Sinan the Architect, was commissioned as the architect of the mosque project, but he couldn’t finish the project as he died in 1599, after two years from the beginning of the construction. Dalgıç Ahmet Çavuş continued to build the mosque, but the project was suspended due to political reasons. Upon the death of Sultan Mehmed III, Sultan Ahmed I, the new Sultan, had no interest in the project, and so the construction was abandoned. Safiye Sultan died in 1619 and left the incomplete mosque behind. Later on, the famous architect Mustafa Agha suggested to Turhan Hatice Sultana, mother of Sultan Mehmed IV, to complete the mosque as an indication of godliness. Turhan Hatice Sultana accepted the suggestion. She also ordered the construction of Spice Bazaar next to the mosque. Within the same year, the construction of the mosque was resumed, and the construction of Spice Bazaar began. In 1663, the mosque was finally completed, and opened for worship in 1665. The mosque was named “New Valide Sultan Mosque”, but the name was shortened to “Yeni Camii” (New Mosque)
Like many other Ottoman mosques, New Mosque was also designed as an imperial mosque complex which included the mosque itself, fountains, mausoleum, market (today’s Spice Bazaar, or Egyptian Bazaar), Turkish bath, a hospital and a primary school. A library was also added to the complex during the sultanate of Sultan Ahmed III. It has 2 minarets, 66 domes and semi domes, which were arranged pyramidal in shape. This dome plan of the New Mosque was inspired from Sinan the Architect’s Şehzade Mosque and Sedefkar Mehmet Agha’s Sultan Ahmed Mosque (Blue Mosque). The minaret is 52m high, while the outer dome’s height is 36m, and the inner dome’s is 17.5m. The courtyard of the mosque is 39m on each side, and a fountain stands in the centre. The interior of the mosque is square shaped and measures 41 meters on each side. It is decorated with blue, green and white İznik tiles. Calligraphic plates line the four corners where the dome meets with the ascending pillars. Like many other Ottoman mosques, the names of the first four khalifahs (Abu Bakr, Umar, Uthman and Ali) are written on these plates.