A.K.A.: Suleyman Mosque, Suleiman's Mosque, süleymaniye cami, Süleymaniye Mosque
One of the most stunning aspects of Ottoman artistry can be found in architecture. The Suleymaniye Mosque of Istanbul, built by Suleyman in honor of his father Selim I, dominates the skyline at the Golden Horn's western bank and is still a major site in Turkey today. It is the second biggest mosque in the city, but is known as the one of the most beautiful and ornate of all the mosques in Istanbul. It was built by Sinan, who was a well renouned architect in the golden age of the Ottomans. Suleyman was so happy with the building that he also made it his own mausoleum, and later on Sinan was buried there as well.
The mosque took seven years to build--from 1550 until 1557 and was its own self contained world in many ways. It contains a large mosque, two mausoleums, six madrassas (schools), a Qur'anic school, a hospital, a hostel, a public kitchen for the poor, a rest stop for caravans, a Turkish bath, and several shops. It has four minarets, as is standard for mosques, and cascading domes. It is basically square in construction with a large dome that is 47 meters high and 27.5 meters wide. There are ornate inscriptions done by Ahmet Karahisari (the most famous calligrapher of the Ottoman Empire) and his pupil Hasan Celebi throughout the mosque. The mihrab (area for prayer toward Mecca) and the mimber (pulpit) are constructed entirely of carved white marble.
Suleyman wrote the building was erected in order "to elevate matters of religion and religious sciences in order to strengthen the mechanisms of worldly sovereignty and to reach happiness in the afterworld." This sort of statement mixing the temporal with the spiritual was in keeping with the legacy of Suleyman, whose most famous accomplishment was to unite Islamic religious law with Ottoman bureaucratic administration during his reign.
The building is still used for prayer today. Women are allowed to enter the mosque without a headscarf but tourists are only allowed about halfway in. Only a very small amount of mosques in the city (namely this mosque and Sultan Ahmet (Blue Mosque) ) will allow women to do that. It is suggested that women who are visiting cover their hair out of respect, but it is not required. People have been politely handed scarves when entering, so if you go I'd imagine you are best off just wearing one yourself. It is required that people who visit don't intervene or interrupt with any prayers that may be going on, however.
Lecture - Dr. Nancy Stockdale at University of Central Florida