Walls of Constantinople
The walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger. They saved the city, and the Byzantine Empire with it, during sieges by the Avar–Sassanian coalition, Arabs, Rus', and Bulgars, among others. The fortifications retained their usefulness even after the advent of gunpowder siege cannons, which played a part in the city's fall to Ottoman forces in 1453 but were not able to breach its walls.
The walls were largely maintained intact during most of the Ottoman period until sections began to be dismantled in the 19th century, as the city outgrew its medieval boundaries. Despite lack of maintenance, many parts of the walls survived and are still standing today. A large-scale restoration program has been underway since the 1980s.
Land walls
Walls of Greek and Roman Byzantium
According to tradition, the city was founded as Byzantium by Greek colonists from the Attic town of Megara, led by the eponymous Byzas, around 658 BC. The city then consisted of a small region around an acropolis located on the easternmost hill. According to the late Byzantine Patria of Constantinople, ancient Byzantium was enclosed by a small wall that began on the northern edge of the acropolis, extended west to the Tower of Eugenios, then went south and west towards the Strategion and the Baths of Achilles, continued south to the area known in Byzantine times as Chalkoprateia, and then turned, in the area of the Hagia Sophia, in a loop towards the northeast, crossed the regions known as Topoi and Arcadianae and reached the sea at the later quarter of Mangana. This wall was protected by twenty-seven towers and had at least two landward gates, one which survived to become known as the Arch of Urbicius, and one where the Milion monument was later located. On the seaward side, the wall was much lower. Although the author of the asserts that this wall dated to the time of Byzas, the French researcher Raymond Janin thinks it more likely that it reflects the situation after the city was rebuilt by the Spartan general Pausanias, who conquered the city in 479 BC. This wall is known to have been repaired, using tombstones, under the leadership of a certain Leo in 340 BC, against an attack by Philip II of Macedon.Byzantium was relatively unimportant during the early Roman period. Contemporaries described it as wealthy, well peopled and well fortified, but that affluence came to an end because the city supported Pescennius Niger in his war against Septimius Severus. According to the account of Cassius Dio, the city held out against Severan forces for three years, until 196, with its inhabitants resorting even to throwing bronze statues at the besiegers when they ran out of other projectiles. Severus punished the city harshly: the strong walls were demolished, and the town was deprived of its civic status, being reduced to a mere village dependent on Heraclea Perinthus. However, appreciating the city's strategic importance, Severus eventually rebuilt it and endowed it with many monuments, including a Hippodrome and the Baths of Zeuxippus, as well as a new set of walls, located some 300–400 m to the west of the old ones. Little is known of the Severan Wall save for a short description of its course by Zosimus and that its main gate was located at the end of a porticoed avenue and shortly before the entrance of the later Forum of Constantine. The wall seems to have extended from near the modern Galata Bridge in the Eminönü quarter south through the vicinity of the Nuruosmaniye Mosque to curve around the southern wall of the Hippodrome, and then going northeast to meet the old walls near the Bosporus. The also mentions the existence of another wall during the siege of Byzantium by Constantine the Great during the latter's conflict with Licinius, in 324. The text mentions that a fore-wall ran near the Philadelphion, located at about the middle of the later, Constantinian city, suggesting the expansion of the city beyond the Severan Wall by this time.
Constantinian walls
Like Severus before him, Constantine began to punish the city for siding with his defeated rival, but he too soon realised the advantages of Byzantium's location. From 324 to 336, the city was thoroughly rebuilt and inaugurated on 11 May 330 under the name of "New Rome" or "Second Rome". Eventually, the city would most commonly be referred to as Constantinople, the "City of Constantine", in dedication to its founder. New Rome was protected by a new wall about 2.8 km west of the Severan wall. Constantine's fortification consisted of a single wall, reinforced with towers at regular distances, which began to be constructed in 324 and was completed under his son Constantius II. Only the approximate course of the wall is known: it began at the Church of St. Anthony at the Golden Horn, near the modern Atatürk Bridge, ran southwest and then southwards, passed east of the great open cisterns of Mocius and of Aspar, and ended near the Church of the Theotokos of the Rhabdos on the Propontis coast, somewhere between the later sea gates of St. Aemilianus and Psamathos.Already by the early 5th century, Constantinople had expanded outside the Constantinian Wall in the extramural area known as the Exokionion or Exakionion. The wall survived during much of the Byzantine period, even though it was replaced by the Theodosian walls as the city's primary defense. An ambiguous passage refers to extensive damage to the city's "inner wall" from an earthquake on 26 January 447, which likely refers to the Constantinian wall. When repairs were being undertaken, to prevent an invasion by Attila, the Blues and Greens, the supporters of chariot-racing teams, supplied 16,000 men between them for the building effort.
Theophanes the Confessor reports renewed earthquake damage in 557. It appears that large parts survived relatively intact until the 9th century: the 11th-century historian Kedrenos records that the "wall at Exokionion", likely a portion of the Constantinian wall, collapsed in an earthquake in 867. Only traces of the wall appear to have survived in later ages, although Alexander van Millingen states that some parts survived in the region of the İsakapı until the early 19th century. In 2018 the construction of Yenikapı Transfer Center unearthed a section of the foundation of the wall of Constantine.
Gates
The names of a number of gates of the Constantinian Wall survive, but scholars debate their identity and exact location.The Old Golden Gate, known also as the Xerolophos Gate and the Gate of Saturninus, is mentioned in the Notitia Urbis Constantinopolitanae, which further states that the city wall itself in the region around it was "ornately decorated". The gate stood somewhere on the southern slopes of the Seventh Hill. Its construction is often attributed to Constantine, but is in fact of uncertain age. It survived until the 14th century, when the Byzantine scholar Manuel Chrysoloras described it as being built of "wide marble blocks with a lofty opening", and crowned by a kind of stoa. In late Byzantine times, a painting of the Crucifixion was allegedly placed on the gate, leading to its later Ottoman name, İsakapı. It was destroyed by an earthquake in 1509, but its approximate location is known through the presence of the nearby İsakapı Mescidi mosque.
The identity and location of the Gate of Atalos are unclear. Cyril Mango identifies it with the Old Golden Gate; van Millingen places it on the Seventh Hill, at a height probably corresponding to one of the later gates of the Theodosian Wall in that area; and Raymond Janin places it further north, across the Lycus and near the point where the river passed under the wall. In earlier centuries, it was decorated with many statues, including one of Constantine, which fell down in an earthquake in 740.
The only gate whose location is known with certainty, aside from the Old Golden Gate, is the Gate of Saint Aemilianus, named in Turkish Davutpaşa Kapısı. It lay at the juncture with the [|sea walls], and served the communication with the coast. According to the Chronicon Paschale, the Church of St Mary of Rhabdos, where the Rod of Moses was kept, stood next to the gate.
The Old Gate of the Prodromos, named after the nearby Church of St John the Baptist, is another unclear case. Van Millingen identifies it with the Old Golden Gate, while Janin considers it to have been located on the northern slope of the Seventh Hill.
The last known gate is the Gate of Melantias, whose location is also debated. Van Millingen considered it to be a gate of the Theodosian Wall, while more recently, Janin and Mango have rebutted this, suggesting that it was located on the Constantinian Wall. While Mango identifies it with the Gate of the Prodromos, Janin considers the name to have been a corruption of the ta Meltiadou quarter, and places the gate to the west of the Mocius cistern. Other authors identified it with the [|Gate of Adrianople] or with the [|Gate of Rhesios].
Theodosian walls
The double Theodosian walls, located about to the west of the old Constantinian wall, were erected during the reign of Emperor Theodosius II, after whom they were named. The work was carried out in two phases, with the first phase erected during Theodosius' minority under the direction of Anthemius, the praetorian prefect of the East, and was finished in 413 according to a law in the Codex Theodosianus. An inscription discovered in 1993 however records that the work lasted for nine years, indicating that construction had already begun, in the reign of Emperor Arcadius. This initial construction consisted of a single curtain wall with towers, which now forms the inner circuit of the Theodosian walls.Both the Constantinian and the original Theodosian walls were severely damaged in two earthquakes, on 25 September 437 and 6 November 447. The latter was especially powerful and destroyed large parts of the wall, including 57 towers. Subsequent earthquakes, including another major one in January 448, compounded the damage. Theodosius II ordered the praetorian prefect Constantine to supervise the repairs, made all the more urgent as the city was threatened by the presence of Attila the Hun in the Balkans. Employing the city's chariot-racing factions in the work, the walls were restored in a record 60 days, according to the Byzantine chroniclers and three inscriptions found in situ. It is at this date that the majority of scholars believe the second, outer wall to have been added, as well as a wide moat opened in front of the walls, but the validity of that interpretation is questionable; the outer wall was possibly an integral part of the original fortification concept.
Throughout their history, the walls were damaged by earthquakes and floods of the Lycus river. Repairs were undertaken on numerous occasions, as testified by the numerous inscriptions commemorating the emperors or their servants who undertook to restore them. The responsibility for these repairs rested on an official variously known as the domestic of the walls or the count of the walls, who employed the services of the city's populace in this task. After the Latin conquest of 1204, the walls fell increasingly into disrepair, and the revived post-1261 Byzantine state lacked the resources to maintain them, except in times of direct threat.