It is called the "Blue Mosque" due to the extensive use of blue Iznik tiles in the interior.
It was the world's only mosque with six minarets until the recent construction of the Haci Omer Sabanci Mosque in Adana, Turkey.
Four massive columns, called "elephant legs" by the locals in Istanbul, support its large dome. This is a solution which was not used by Sinan in the Suleymaniye Mosque. Even though these massive columns enhance the strength of the building, they also reduce the interior space, as well as the visibility within the mosque.
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