Hagia Sophia Grand Mosque

Completed in AD 537, this structure is a primary example of Byzantine architecture. It was originally built as a Greek Orthodox patriarchal cathedral and served this role until the Ottoman conquest in 1453, when it was converted into a mosque. After being designated as a museum in 1935, the site was reconverted into a mosque in 2020. The building is recognized as a UNESCO World Heritage Site.

The design is noted for its innovative pendentive dome, which was a groundbreaking feat in architectural history. Key architects involved in its construction and later restoration include Isidore of Miletus, Anthemius of Tralles, Trdat the Architect, and Mimar Sinan. The interior features extraordinary golden mosaics and architectural characteristics that represent both Christian and Islamic heritage.

The site is open to the public and includes access to the mosque and a dedicated History & Experience Museum. Audio commentary is available in multiple languages. Long queues are common for entry, though skip-the-line options are available for the museum experience.