557 Constantinople earthquake
The 557 Constantinople earthquake took place on the night of December 14. This earthquake, described in the works of Agathias, John Malalas, and Theophanes the Confessor, caused great damage to Constantinople, then capital of the Byzantine Empire in a region frequently afflicted with earthquakes. More minor quakes had preceded the large event, including two in April and October respectively. The main quake in December was of unparalleled ferocity, and "almost completely razed" the city. It caused damage to the Hagia Sophia which contributed to the collapse of its dome the next year, as well as damaging the walls of Constantinople to the extent that Hun invaders were able to penetrate it with ease the following season.