With its huge dome and immense dimensions, Hagia Sophia was a surpassed. Sinan accomplished this difficult task. He reached to an excellence far-surpassed Hagia Sophia’s heavy monumentality (see Suleymaniye and Selimiye Mosques). The achievement of Anthemios real challenge for the Ottoman architects. It was an inspiration source and also a representative of a conquered culture, which was to be and Isidoros was the placement of a huge dome (32.5 m.) over an oblong basilica. Entrance vestibules (narthex) lead to a breathtaking central space. Four exedrae, apse and two semidomes on the east and west, the gallery arcades on the north and south, and the dome above circumscribe this lofty space. Four huge pillars and bulky buttresses attached to them on the outside support the dome. The use of a basilica that stretch below the dome with narthexes, a nave, aisles and galleries causes the fragmentation of the interior space. Aside the nave, the components of this basilica are dark and secondary spaces without direct interrelationship with the domed central piece. However, the building is really imposing from the centre. Its dome is like a shell soaring in the sky. The windows at its edges (clerestory windows) and the enormous height and width of the dome create this impression. The dome of Hagia Sophia substantiates a cosmological notion: heavenly dome. It is configurated as a disjunct segment of the structure. Together with all other subsidiary sections attached to the nave it participates in the “detached space” of the building. Contrastingly, the dome of a monumental Ottoman mosque limits and fixes an interior space. It is an inseparable part of the architectural composition. Unlike the dome of Hagia Sophia, Ottoman dome intermingles with the lower structure. Sinan’s Selimiye is a very good example to illustrate this. In Sinan’s structures, the subsidiary spaces are diminished and amalgamated to the central space. Even in Suleymaniye, which is the closest mosque to Hagia Sophia, the fragmented space understanding is suppressed (see Suleymaniye Mosque). It is erroneous to say that classical Ottoman mosques copied Hagia Sophia. But, it is true to say that Hagia Sophia’s monumentality was a source of inspiration. Hagia Sophia is a summation of Roman and Early Christian architecture in a huge scale. There are also some decorative elements borrowed from Sassanian art. But, its architecture is essentially Roman in style. Ottoman architecture of the sixteenth century created a style of its own, which is called “classical”. The Ottoman architect of this period employed almost every architectural and decorative element flourished in the lands along the Mediterranean Sea. His main sources were Roman, Early Islamic, Seljukid and early Ottoman inventions. The architects of Hagia Sophia and Ottoman Classical mosques had distinct aspirations, which helped the accomplishment of two different types of monumentality. Therefore, in a single city, we have an unbelievably rich heritage of local traditions expressed in such gigantic dimensions.