Over the course of its history, Hagia Sophia, situated in Istanbul, Turkey, has functioned as both a basilica and mosque and is now museum. Famous for its massive dome, the building is considered to be one of the finest examples of Byzantine architecture in the world.
Constructed between 532 and 537 AD, the building had two architects, Isidore of Miletus and Anthemius of Tralles. The building originally served as the church of the Patriarch of Constantinople. When the Ottoman Turks conquered the city in 1453, they converted Hagia Sophia into a Mosque. In 1935, the first Turkish president Mustafa Kemal Atuturk transformed the building into a museum.
The Dome
Hagia Sophia's architectural focal point is its dome due to its innovative construction and perceived beauty. The dome uses "pendentives," which allow the round dome to transition into the square shape of its supporting pier. They are considered by historians to be both aesthetically pleasing and a structural breakthrough as they restrain the lateral forces of the dome, propelling its weight downward.
The builders also placed forty windows around the base of the dome, which lends Hagia Sophia which allows light to reflect through the building's interiors.