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 (corresponding to the modern site of the
Topkapı Palace). 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 (the first part of the later
Mese) 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 (
proteichisma) 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 (15
stadia) 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 (r. 337–361). 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 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 ("Gate of
Jesus"). 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 At[t]alos (, ) are unclear.
Cyril Mango identifies it with the Old Golden Gate; The only gate whose location is known with certainty, aside from the Old Golden Gate, is the Gate of Saint Aemilianus (, ), named in Turkish . 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 (called , "the Forerunner", in Greek), 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. 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.
Theodosian walls The double Theodosian walls (,
teichos Theodosiakon), 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. 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.
Course and topography In their present state, the Theodosian walls stretch for about from south to north, from the "Marble Tower" (), also known as the "Tower of
Basil and
Constantine" (Greek: ) on the
Propontis coast to the area of the
Palace of the Porphyrogenitus () in the
Blachernae quarter. The outer wall and the moat terminate even earlier, at the height of the Gate of Adrianople. The section between the Blachernae and the Golden Horn does not survive since the line of the walls was later brought forward to cover the suburb of Blachernae, and its original course is impossible to ascertain, as it lies buried beneath the modern city. From the Sea of Marmara, the wall turns sharply to the northeast until it reaches the Golden Gate, at about 14 m above sea level. From there and until the Gate of Rhegion the wall follows a more or less straight line to the north, climbing the city's Seventh Hill. From there the wall turns sharply to the northeast, climbing up to the Gate of St. Romanus, located near the peak of the Seventh Hill at some 68 m above sea level. From there the wall descends into the valley of the river Lycus, where it reaches its lowest point at 35 m above sea level. Climbing the slope of the Sixth Hill, the wall then rises up to the Gate of Charisius or Gate of Adrianople, at some 76 m height. Between the outer wall and the moat (, ) there stretched an outer terrace, the (), while a low breastwork crowned the moat's eastern escarpment. Access to both terraces was possible through
posterns on the sides of the walls' towers. The inner wall is a solid structure, 4.5–6 m thick and 12 m high. It is faced with carefully cut limestone blocks, while its core is filled with mortar made of lime and crushed bricks. Between seven and eleven bands of
brick, approximately 40 cm thick, traverse the structure, not only as a form of decoration, but also strengthening the cohesion of the structure by bonding the stone façade with the mortar core, and increasing endurance to
earthquakes. The wall was strengthened with 96 towers, mainly square but also a few octagonal ones, three hexagonal and a single pentagonal one. They were 15–20 m tall and 10–12 m wide, and placed at irregular distances, according to the rise of the terrain: the intervals vary between 21 and 77 m, although most curtain wall sections measure between 40 and 60 meters. Each tower had a battlemented terrace on the top. Its interior was usually divided by a floor into two chambers, which did not communicate with each other. The lower chamber, which opened through the main wall to the city, was used for storage, while the upper one could be entered from the wall's walkway, and had windows for view and for firing projectiles. Access to the wall was provided by large ramps along their side. The lower floor could also be accessed from the by small posterns. Generally speaking, most of the surviving towers of the main wall have been rebuilt in Byzantine or Ottoman times, and only the foundations of some are of original Theodosian construction. Furthermore, while until the
Komnenian period, the reconstructions largely remained true to the original model, later modifications ignored the windows and embrasures on the upper story and focused on the
tower terrace as the sole
fighting platform. '', the space between the inner and outer walls|alt=Photograph showing a stone bastion in the front, with a wall to the left and right and a space in between The outer wall was 2 m thick at its base, and featured arched chambers on the level of the , crowned with a battlemented walkway, reaching a height of 8.5–9 m. Access to the outer wall from the city was provided either through the main gates or through small
posterns on the base of the inner wall's towers. The outer wall likewise had towers, situated approximately midway between the inner wall's towers, and acting in supporting role to them. Of the outer wall's towers, 62 survive. With few exceptions, they are square or crescent-shaped, 12–14 m tall and 4 m wide. They featured a room with windows on the level of the , crowned by a battlemented terrace, while their lower portions were either solid or featured small posterns, which allowed access to the outer terrace. The moat was situated at a distance of about 20 m from the outer wall. The moat itself was over 20 m wide and as much as 10 m deep, featuring a 1.5 m tall
crenellated wall on the inner side, serving as a first line of defence. Transverse walls cross the moat, tapering towards the top so as not to be used as bridges. Some of them have been shown to contain pipes carrying water into the city from the hill country to the city's north and west. Their role has therefore been interpreted as that of aqueducts for filling the moat and as dams dividing it into compartments and allowing the water to be retained over the course of the walls. According to
Alexander van Millingen, there is little direct evidence in the accounts of the city's sieges to suggest that the moat was ever actually flooded. In the sections north of the Gate of St. Romanus, the steepness of the slopes of the Lycus valley made the construction maintenance of the moat problematic; it is probable therefore that the moat ended at the Gate of St. Romanus, and did not resume until after the Gate of Adrianople. The weakest section of the wall was the so-called
Mesoteichion (, "middle wall"). Modern scholars are not in agreement over the extent of that portion of the wall, which has been variously defined from as narrowly as the stretch between the Gate of St. Romanus and the Fifth Military Gate (by A. M. Schneider) to as broad as from the Gate of Rhegion to the Fifth Military Gate (by B. Tsangadas) or from the Gate of St. Romanus to the Gate of Adrianople (by van Millingen). The walls survived the entire Ottoman period and appeared in travelogues of foreign visitors to Constantinople/Istanbul. A 16th-century Chinese geographical treatise, for example, recorded, "Its city has two walls. A sovereign prince lives in the city ...".
Gates The wall contained nine main gates, which pierced both the inner and the outer walls, and a number of smaller
posterns. The exact identification of several gates is debatable for a number of reasons. The Byzantine chroniclers provide more names than the number of the gates, the original Greek names fell mostly out of use during the Ottoman period, and literary and archaeological sources provide often contradictory information. Only three gates, the Golden Gate, the Gate of Rhegion and the Gate of Charisius, can be established directly from the literary evidence. In the traditional nomenclature, established by Philipp Anton Dethier in 1873, the gates are distinguished into the "Public Gates" and the "Military Gates", which alternated over the course of the walls. According to Dethier's theory, the former were given names and were open to civilian traffic, leading across the moat on bridges, and the latter were known by numbers, were restricted to military use and led only to the outer sections of the walls. Today that division is, if retained at all, only a historiographical convention. There is sufficient reason to believe that several of the "Military Gates" were also used by civilian traffic. In addition, a number of them have proper names, and the established sequence of numbering them, based on their perceived correspondence with the names of certain city quarters lying between the Constantinian and Theodosian walls, which have numerical origins, has been shown to be erroneous. For instance, the
Deuteron, the "Second" Quarter, was located not in the southwest behind the Gate of the
Deuteron or "Second Military Gate", as would be expected, but in the northwestern part of the city.
First Military Gate The gate is a small postern, which lies at the first tower of the land walls, at the junction with the sea wall. It features a wreathed
Chi-Rhō Christogram above it. It is also known as the ('Gate of the Tannery') in reference to the nearby leather works.
Golden Gate Following the walls from south to north, the Golden Gate (,
Chryseia Pylē; ; ), is the first gate to be encountered. It was the main ceremonial entrance into the capital, used especially for the occasions of a
triumphal entry of an emperor into the capital on the occasion of military victories or other state occasions such as coronations. On rare occasions, as a mark of honor, the entry through the gate was allowed to non-imperial visitors:
papal legates (in 519 and 868) and, in 710, to
Pope Constantine. The Gate was used for triumphal entries until the
Komnenian period; thereafter, the only such occasion was the entry of
Michael VIII Palaiologos into the city on 15 August 1261, after its reconquest from the
Latins. With the progressive decline in Byzantium's military fortunes, the gates were walled up and reduced in size in the later
Palaiologan period, and the complex converted into a citadel and refuge. The Golden Gate was emulated elsewhere, with several cities naming their principal entrance thus, for instance
Thessaloniki (also known as the Vardar Gate) or
Antioch (the Gate of Daphne), The date of the Golden Gate's construction is uncertain, with scholars divided between
Theodosius I and
Theodosius II. Earlier scholars favored the former, but the current majority view tends to the latter, meaning that the gate was constructed as an integral part of the Theodosian walls. The debate has been carried over to a now-lost Latin inscription in metal letters that stood above the doors and commemorated their gilding in celebration of the defeat of an unnamed usurper: (English translation) While the legend has not been reported by any known Byzantine author, an investigation of the surviving holes wherein the metal letters were riveted verified its accuracy. It also showed that the first line stood on the western face of the arch, while the second on the eastern. According to the current view, this refers to the usurper
Joannes (r. 423–425), The gate, built of large square blocks of polished white
marble fitted together without cement, has the form of a triumphal arch with three arched gates, the middle one larger than the two others. The gate is flanked by large square towers, which form the 9th and 10th towers of the inner Theodosian wall. With the exception of the central portal, the gate remained open to everyday traffic. The structure was richly decorated with numerous statues, including a statue of Theodosius I on an elephant-drawn
quadriga on top, echoing the
Porta Triumphalis of Rome, which survived until it fell down in the
740 Constantinople earthquake. Other sculptures were a large cross, which fell in an earthquake in 561 or 562; a
Victory, which was cast down in the reign of
Michael III; and a crowned
Fortune of the city. The main gate itself was covered by an outer wall, pierced by a single gate, which in later centuries was flanked by an ensemble of
reused marble reliefs. According to descriptions of
Pierre Gilles and English travelers from the 17th century, these reliefs were arranged in two tiers, and featured mythological scenes, including the
Labours of Hercules. These reliefs, lost since the 17th century with the exception of some fragments now in the
Istanbul Archaeological Museum, were probably put in place in the 9th or 10th centuries to form the appearance of a triumphal gate. According to other descriptions, the outer gate was also topped by a statue of
Victory, holding a crown. Despite its ceremonial role, the Golden Gate was one of the strongest positions along the walls of the city and withstood several attacks during the various sieges. With the addition of transverse walls on the
peribolos between the inner and outer walls, it formed a virtually separate fortress. Its military value was recognized by
John VI Kantakouzenos (r. 1347–1354), who records that it was virtually impregnable, capable of holding provisions for three years and defying the whole city if need be. He repaired the marble towers and garrisoned the fort, but had to surrender it to
John V Palaiologos (r. 1341–1391) when he abdicated in 1354. John V undid Kantakouzenos' repairs and left it unguarded, but in 1389–90 he too rebuilt and expanded the fortress, erecting two towers behind the gate and extending a wall some 350 m to the sea walls, thus forming a separate fortified
enceinte inside the city to serve as a final refuge. In the event, John V was soon after forced to flee there from a coup led by his grandson,
John VII. The fort held out successfully in the subsequent siege that lasted several months, and in which cannons were possibly employed. In 1391 John V was compelled to raze the fort by Sultan
Bayezid I (r. 1389–1402), who otherwise threatened to blind his son
Manuel, whom he held captive. Emperor
John VIII Palaiologos attempted to rebuild it in 1434, but was thwarted by threats from Sultan
Murad II. According to one of the many Greek legends about the Constantinople's fall to the Ottomans, when the Turks entered the city, an angel rescued the emperor
Constantine XI Palaiologos, turned him into marble and placed him in a cave under the earth near the Golden Gate, where he waits to
be brought to life again to conquer the city back for Christians. The legend explained the later walling up of the gate as a Turkish precaution against this prophecy.
Yedikule Fortress After his
conquest of Constantinople in 1453, Sultan
Mehmed II built a new fort in 1458. By adding three larger towers to the four pre-existing ones (towers 8 to 11) on the inner Theodosian wall, he formed the
Fortress of the Seven Towers ( or
Zindanları). It lost its function as a gate, and for much of the Ottoman era, it was used as a treasury, archive, and state prison. It eventually became a museum in 1895. Its name derives from the fact that it led to a wooden
circus (
amphitheatre) outside the walls. The gate complex is approximately 12 m wide and almost 20 m high, while the gate itself spans 5 m. According to a story related by
Niketas Choniates, in 1189 the gate was walled off by Emperor
Isaac II Angelos, because according to a prophecy, it was this gate that Western Emperor
Frederick Barbarossa would enter the city through. It was re-opened in 1346, but closed again before the siege of 1453 and remained closed until 1886, leading to its early Ottoman name,
Kapalı Kapı ("Closed Gate").
Second Military Gate The gate () is located between towers 30 and 31, little remains of the original gate, and the modern reconstruction may not be accurate.
Gate of the Spring The Gate of the Spring or Pēgē Gate ( in Greek) was named after a popular monastery outside the walls, the
Zōodochos Pēgē ("
Life-giving Spring") in the modern suburb of
Balıklı. Its modern Turkish name, Gate of
Selymbria (Tr.
Silivri Kapısı or
Silivrikapı, Gk. ), appeared in Byzantine sources shortly before 1453. It lies between the heptagonal towers 35 and 36, which were extensively rebuilt in later Byzantine times: its southern tower bears an inscription dated to 1439 commemorating repairs carried out under
John VIII Palaiologos. The gate arch was replaced in the Ottoman period. In addition, in 1998 a subterranean basement with 4th/5th century reliefs and tombs was discovered underneath the gate. Van Millingen identifies this gate with the early Byzantine Gate of Melantias (Πόρτα Μελαντιάδος), but more recent scholars have proposed the identification of the latter with one of the
gates of the city's original Constantinian wall.
Third Military Gate The Third Military Gate (), named after the quarter of the
Triton ("the Third") that lies behind it, is situated shortly after the Pege Gate, exactly before the C-shaped section of the walls known as the "
Sigma", between towers 39 and 40. It has no Turkish name, and is of middle or late Byzantine construction. The corresponding gate in the outer wall was preserved until the early 20th century, but has since disappeared. It is very likely that this gate is to be identified with the Gate of Kalagros ().
Gate of Rhegion Modern
Yeni Mevlevihane Kapısı, located between towers 50 and 51 is commonly referred to as the Gate of Rhegion () in early modern texts, allegedly named after the suburb of Rhegion (modern
Küçükçekmece), or as the Gate of Rhousios () after the
hippodrome faction of the Reds (,
rhousioi) which was supposed to have taken part in its repair. From Byzantine texts it appears that the correct form is Gate of Rhesios (), named according to the 10th-century
Suda lexicon after an ancient general of Greek
Byzantium. A.M. Schneider also identifies it with the Gate of Myriandr[i]on or Polyandrion ("Place of Many Men"), possibly a reference to its proximity to a cemetery. It is the best-preserved of the gates, and retains substantially unaltered from its original, 5th-century appearance.
Fourth Military Gate The so-called Fourth Military Gate stands between towers 59 and 60, and is currently walled up. Recently, it has been suggested that this gate is actually the Gate of St. Romanus, but the evidence is uncertain.
Gate of St. Romanus The Gate of St. Romanus () was named so after a nearby church and lies between towers 65 and 66. It is known in Turkish as
Topkapı, the "Cannon Gate", after the great Ottoman cannon, the "
Basilic", that was placed opposite it during the 1453 siege. With a gatehouse of 26.5 m, it is the second-largest gate after the Golden Gate.
Fifth Military Gate The Fifth Military Gate () lies immediately to the north of the
Lycus stream, between towers 77 and 78, and is named after the quarter of the
Pempton ("the Fifth") around the Lycus. It is heavily damaged, with extensive late Byzantine or Ottoman repairs evident. It is also identified with the Byzantine Gate of [the Church of] St. Kyriake, and called
Sulukulekapı ("Water-Tower Gate") or
Hücum Kapısı ("Assault Gate") in Turkish, because there the decisive breakthrough was achieved on the morning of 29 May 1453. In the late 19th century, it appears as the
Örülü kapı ("walled gate"). Some earlier scholars, like
J. B. Bury and
Kenneth Setton, identify this gate as the "Gate of St. Romanus" mentioned in the texts on the final siege and fall of the city. If this theory is correct, the last Byzantine emperor,
Constantine XI, died in the vicinity of this gate during the final assault of 29 May 1453. Support to this theory comes from the fact that the particular gate is located at a far weaker section of the walls than the "cannon gate", and the most desperate fighting naturally took place here.
Gate of Charisius The Gate of Char[i]sius (), named after the nearby early Byzantine monastery founded by a
vir illustris of that name, was, after the Golden Gate, the second-most important gate. This gate stands on top of the sixth hill, which was the highest point of the old city at 77 meters. It has also been suggested as one of the gates to be identified with the Gate of Polyandrion or Myriandrion (), because it led to a cemetery outside the walls. The last Byzantine emperor,
Constantine XI, established his command here in 1453.
Minor gates and posterns Known posterns are the , a small postern after the Yedikule Fort (between towers 11 and 12), and the gates between towers 30/31, already walled up in Byzantine times, while others consider it an Ottoman addition.
Kerkoporta According to the historian
Doukas, on the morning of 29 May 1453, the small postern called
Kerkoporta was left open by accident, allowing the first fifty or so
Ottoman troops to enter the city. The Ottomans raised their banner atop the inner wall and opened fire on the Greek defenders of the
peribolos below. This spread panic, beginning the rout of the defenders and leading to the
fall of the city. In 1864, the remains of a postern located on the outer wall at the end of the Theodosian walls, between tower 96 and the so-called
Palace of the Porphyrogenitus, were discovered and identified with the Kerkoporta by the Greek scholar A.G. Paspates. Later historians, like van Millingen and
Steven Runciman have accepted this theory as well. But excavations at the site have uncovered no evidence of a corresponding gate in the inner wall (now vanished) in that area, and it may be that Doukas' story is either invention or derived from an earlier legend concerning the
Xylokerkos Gate, which several earlier scholars also equated with the
Kerkoporta.
Later history The Theodosian walls have been called the "most monumental and successful" fortifications of
late antiquity. According to
The Cambridge Ancient History, they were "perhaps the most successful and influential city walls ever built – they allowed the city and its emperors to survive and thrive for more than a millennium, against all strategic logic, on the edge of [an] extremely unstable and dangerous world...". They remained effective into the fifteenth century; during the
1422 siege of the city, Ottoman cannon fired on the part of the wall between the Golden Gate and the Gate of Romanos, but were unable to breach the walls. At no point during the final siege of the city in 1453, a period of almost two months, were the Ottoman artillery able to breach the wall. The city fell on 29 May after a total of seven weeks of siege: at this time, it was reckoned to have the strongest fortifications of any city in Europe. After the capture of the city, one of Mehmed's first actions was to order the repair of the walls. The wall was later damaged in the
1766 Istanbul earthquake.
Walls of Blachernae in the background, as they appear today in suburban
Istanbul|alt=Photograph of a city scene; large, ruined walls can be seen to the right. The walls of Blachernae connect the Theodosian walls, which terminate at the height of the
Palace of the Porphyrogenitus (), with the sea wall at the
Golden Horn. They consist of a series of single walls built in different periods, which cover the suburb of
Blachernae. Generally they are about 12–15 meters in height, thicker than the Theodosian walls and with more closely spaced towers. Situated on a steep slope, they lacked a moat, except on their lower end towards the Golden Horn, where Emperor
John VI Kantakouzenos had one dug. The question of the original fortifications in this area has been examined by several scholars, and several theories have been proposed as to their course. It is known from the
Notitia Urbis Constantinopolitanae that the XIV region, which comprised Blachernae, stood apart and was enclosed all around by a wall of its own. Further it is recorded that originally, and at least as late as the
Avar-Persian siege of 626, when they were burned down, the important sanctuaries of
Panagia Blachernitissa and St. Nicholas lay just outside the quarter's fortifications. Traces of the quarter's walls have been preserved, running from the area of the Porphyrogenitus Palace in straight line to the so-called
Prison of Anemas. The original fortified quarter can thereby be roughly traced to have comprised the two northern spurs of the city's Seventh Hill in a triangle, stretching from the Porphyrogenitus Palace to the Anemas Prison, from there to the church of St. Demetrios Kanabos and thence back to the Porphyrogenitus Palace. These fortifications were apparently older than the Theodosian walls, probably dating to sometime in the 4th century, and were then connected to the new city walls under Theodosius II, with the western wall forming the outer face of the city's defenses and the eastern wall fell into disrepair. Today, the Theodosian walls are connected in the vicinity of the Porphyrogenitus Palace with a short wall, which features a postern, probably the postern of the Porphyrogenitus () recorded by John VI Kantakouzenos, and extends from the palace to the first tower of the so-called Wall of Manuel Komnenos. As recorded by the historian
Niketas Choniates, that wall was built by Emperor
Manuel I Komnenos () as a protection to the imperial
Palace of Blachernae, since the late 11th century the emperors' preferred residence. It is an architecturally excellent fortification, consisting of a series of arches closed on their outer face, built with masonry larger than usual and thicker than the Theodosian walls, measuring some 5 m at the top. It features eight round and octagonal towers, while the last is square. The wall stretches for 220 m, beginning at an almost right angle from the line of the Theodosian walls, going westward up to the third tower and then turning sharply north. The Komnenian wall lacks a moat, since the difficult terrain of the area makes it unnecessary. The wall features one postern, between the second and third towers, and one large gate, the ("Crooked Gate"), between the sixth and seventh towers. Its Turkish name comes from the sharp bend of the road in front of it to pass around a tomb which is supposed to belong to Hazret Hafiz, a companion of
Muhammad who died there during the
first Arab siege of the city. It is usually, but not conclusively, identified with the Byzantine Kaligaria Gate (, ), the "Gate of the Bootmakers' Quarter" ( Latin
caliga, "sandal"). From the last tower of the Wall of Manuel Komnenos to the so-called Prison of Anemas stretches another wall, some 150 m in length, with four square towers. It is probably of later date, and of markedly inferior quality than the Komnenian wall, being less thick and with smaller stones and brick tiles utilized in its construction. It also bears inscriptions commemorating repairs in 1188, 1317 and 1441. A walled-up postern after the second tower is commonly identified with the Gyrolimne Gate (, ), named after the
Argyra Limnē, the "Silver Lake", which stood at the head of the Golden Horn. It probably serviced the Blachernae Palace, as evidenced by its decoration with three imperial busts. Schneider however suggests that the name could refer rather to the
Eğri Kapı. Then comes the outer wall of the Anemas Prison, which connects to a double stretch of walls. The outer wall is known as the Wall of Leo, as it was constructed by
Leo V the Armenian (r. 813–820) in 813 to safeguard against the siege by the
Bulgarian ruler
Krum. This wall was then extended to the south by
Michael II (r. 820–829). The wall is a relatively light structure, less than 3 m thick, buttressed by arches which support its
parapet and featuring four towers and numerous loopholes. Behind the Leonine Wall lies an inner wall, which was renovated and strengthened by the additions of three particularly fine hexagonal towers by Emperor
Theophilos (r. 829–842). The two walls stand some 26 m apart and are pierced by a gate each, together comprising the Gate of Blachernae (,
porta tōn Blachernōn). The two walls form a fortified enclosure, called the or ("bracelet") of Blachernae () by the Byzantines, and known after the Ottoman capture of the city in Greek as the (Πενταπύργιον, "Five Towers"), in allusion to the (Gk. ) fortress. The inner wall is traditionally identified by scholars like van Millingen and Janin with the Wall of Heraclius, built by Emperor
Heraclius (r. 610–641) after the Avar–Persian siege to enclose and protect the Church of the Blachernitissa. Schneider identified it in part with the
Pteron (Πτερόν, "wing"), built at the time of Theodosius II to cover the northern flank of the Blachernae (hence its alternate designation as , "
outwork") from the Anemas Prison to the Golden Horn. Consequently, Schneider transferred the identity of the Heraclian Wall on the short stretch of sea wall directly attached to it to its east, which displays a distinct architecture. The identity of the
Pteron remains an unresolved question among modern scholars. Another, short wall was added in later times, probably in the reign of Theophilos, stretching from the junction of the land and sea walls to the sea itself, and pierced by the so-called Wooden Gate (, , or , ). Both this wall and the gate were demolished in 1868. ==Preservation and restoration work==