Byzantium

The rebirth of the Byzantine Empire.

Byzantium rose to power after the fall of the Roman Empire. Also known as the Eastern Roman Empire, the capital city of Constantinople was founded in 330, and continued on the traditions and engineering greatness of Rome. Its wall was the most impenetrable fortifications that the world had seen. While them empire managed to conquer much of the land lost by the western empire, the empire went through many periods of turmoil. During the times the empire would gain and lose much of its territories until Constantinople fell to the Ottoman Empire in 1453.

The Hagia Sophia.

The Hagia Sophia is Byzantium's most famous structure, and the only one that still stands today. Located in the capital Constantinople, known today as Istanbul, it was built by emperor Justinian as an Eastern Orthodox Church. The structure rises 180 feet high, and has a vast interior complex and many stone columns. The dome of the Hagia Sophia is the most well known part of the structure. It was the first structure in the world to use pendentives, wall segments that attach to the dome at an angle wallowing for the domes weight to be spread evenly among the walls of the structure.