Constantinople
Constantinople (; ) was the capital city of the Roman/Byzantine Empire (330–1204 and 1261–1453), and also of the brief Crusader state known as the Latin Empire (1204–1261), until finally falling to the Ottoman Empire (1453–1923). It was reinaugurated in 324 from ancient Byzantium as the new capital of the Roman Empire by Emperor Constantine the Great, after whom it was named, and dedicated on 11 May 330. The city was located in what is now the European side and the core of modern Istanbul.
Walls of Constantinople
Galata, then the suburb of "Sykai", was an integral part of the city by the early 5th century: the "Notitia Urbis Constantinopolitanae" of ca. 425 names it as the city's 13th region. It was probably fortified with walls in the 5th century, and under Justinian I it was granted the status of a city. The settlement declined and disappeared after the 7th century, leaving only the great tower (the "kastellion tou Galatou") in modern Karaköy, that guarded the chain extending across the mouth of the Golden Horn. After the sack of the city in 1204, Galata became a Venetian quarter, and later a Genoese extraterritorial colony, effectively outside Byzantine control. Despite Byzantine opposition, the Genoese managed to surround their quarter with a moat, and by joining their castle-like houses with walls they created the first wall around the colony. The Galata Tower, then called "Christea Turris" ("Tower of Christ"), and another stretch of walls to its north were built in 1349. Further expansions followed in 1387, 1397 and 1404, enclosing an area larger than that originally allocated to them, stretching from the modern district of Azapkapı north to Şişhane, from there to Tophane and thence to Karaköy. After the Ottoman conquest, the walls were maintained until the 1870s, when most were demolished to facilitate the expansion of the city. Today only the Galata Tower, visible from most of historical Constantinople, remains intact, along with several smaller fragments.