Standing on the crest of Istanbul's Seraglio Hill, commanding a magnificent view of the Bosphorus and Golden Horn, Hagia Sophia is one of the world's greatest architectural monuments. First constructed as the principal church of Constantinople in the fourth century, and destroyed twice by fire, Hagia Sophia was rebuilt by Justinian the Great in the mid-sixth century. Its soaring dome and arches, adorned with luminous gold mosaic-work and gleaming marbles, inspired awe among generations of visitors. Following the Ottoman conquest of Constantinople in 1453, Justinian's church was divested of its Christian decoration and was converted to a mosque. Fitted with a mihrab, minbar and minarets, it ranked as one of the most important imperial mosques in Istanbul until 1935, when it was secularised. Converted to a museum, its centuries-long use as a place of worship came to a close. Fully illustrated and replete with detail, this guide to Hagia Sophia traces the history of this majestic building and describes its architectural and artistic development, from its foundation to the present day.