the greatest Church in the ancient Christian world

http://www.sights-and-culture.com/Turkey/Hagia-Sophia.html

532-537 emperor Justinian I erected the greatest Church in the ancient Christian world. The bold structure was a combination of Roman Basilica and domed Roman central building, the central element of which was a dome with a diameter of 101,7 ft (31 m) and a height of 160,7 ft. (49 m) after the example of Hadrian's Pantheon in Rome. Neither in Byzantine nor Osmane days this dimension ever was surpassed. After several seismic shocks however the dome imploded in 558. The dome we see today was consecrated in 562. The dome we see today is 23 ft (7 m) higher and was consecrated in 562.