Why is Hagia Sophia considered an important example of Byzantine architecture?

The Hagia Sophia is considered a pinnacle of Byzantine architecture because it represents a wholly original synthesis of two distinct architectural forms: the longitudinal basilica and the centralized building.12

Commissioned by Emperor Justinian I and completed in 537 CE by architects Anthemius of Tralles and Isidorus of Miletus, the structure is defined by its massive 105-foot main dome. This dome is supported by pendentives—spherical triangles that transition the weight from a square base to a circular dome. This innovation transformed building practices from relying on sheer mass to an "organic architecture" where structural thrust is balanced by counter-thrust.12

The interior design further enhances its significance. By piercing the base of the dome and the curtain walls with windows, the architects created an effect where the canopy appears to float on air, obscuring the structural supports. While it served as the model from which Byzantine architecture developed, the Hagia Sophia remained a unique achievement that was never emulated in scale or design by later Byzantine builders.12