This grand bubble of masonry, one of the great and defining features of Istanbul's skyline, was constructed between 1609 and 1617 by Sultan Ahmet I, who was not only driven by a desire to leave behind an imperial namesake mosque, but was also determined to build a monument to rival the Ayasofya. So great was the Sultan's ambition that he had one unfortunate architect executed before finally choosing Mehmet Aga, probably a student of Sinan, who came up with a plan commonly accepted as impossible to build. The design is a scheme of successively descending smaller domes that addresses the problem of creating a large, covered interior space. The overall effect is one of such great harmony, grace, and power that it's impossible to walk away from this building unaffected.
Several legends are associated with the construction of the six minarets. One says that the sultan's desire for gold minarets -- altin in Turkish -- was understood as alti, or six. Whatever the reasoning, the construction challenged the preeminence of the mosque in Mecca, which at the time also had six minarets. The ensuing scandal, both in and out of Istanbul, resulted in the sultan's ordering the construction of a seventh minaret at the Kaa'ba.
The mosque was completed after just over 6 1/2 years of work and to this day remains one of the finest examples of classical Ottoman architecture. The original complex included a soup kitchen, a medrese (Muslim theological school), a primary school, a hospital, and a market. A türbe, or mausoleum, stands at the corner of the grounds near the Hippodrome and Sultanahmet Park, and houses the remains of Sultan Ahmet I; his wife, Kösem; and three of his sons. It also contains some fine examples of calligraphy on cobalt-blue Iznik tile.
The main entrance (for worshipers; tourists must enter from a portal on the south side) is off the Hippodrome, beneath the symbolic chain that required even the sultan to bow his head when he arrived on horseback. Walk straight through the garden up to the main marbled courtyard of the mosque and you'll see an ablution fountain, no longer in use. The working ablution fountains are located at the ground level of the northern facade facing the Ayasofya. Visitors should enter from the opposite side (from the Hippodrome entrance, follow the garden path diagonally to your right to the south side of the mosque).
If you plan your visit during the morning hours when the sun is still angled from the east, the first effect once inside will be one of blindness as the light penetrates the stained glass, creating an illusion of false darkness. As your eyes adjust, the swirling blues, greens, reds, and yellows from the tile and stained glass increase the impression of immensity and grandeur. The abundant use of decorative tile represents the pinnacle of Iznik tile craftsmanship, evident in the rich yet subtle blues and greens in traditional Ottoman patterns of lilies, tulips, and carnations. The overall dominance of blue prompted the mosque's early visitors to label it the Blue Mosque, a name that sticks to this day.
Lateral half domes resting on enormous elephantine columns (actually called elephant-foot pillars) enhance the sense of open space, but critics contend that the pillars are too overbearing and cumbersome. The elegant medallions facing the mihrab bear the names of Allah and Mohammed; the ones opposite are decorated with the names of the first four caliphs who ruled the Islamic world.
Did You Know? -- Approximately 21,000 tiles were used to decorate the Blue Mosque.