Walls of Constantinople

Walls of Constantinople
Istanbul, Turkey
Map showing Constantinople and its walls during the Byzantine era
Walls of Constantinople
Coordinates	41°00′44″N 28°58′34″E / 41.0122°N 28.9760°E / 41.0122; 28.9760
Type	Walls
Height	Up to 12 m
Site information
Owner	Turkey
Controlled by	Roman Empire, Byzantine Empire, Latin Empire, Ottoman Empire
Open to the public	Yes
Condition	Land walls partly ruined, sea walls largely torn down; Restoration work underway by the Istanbul Municipality.
Site history
Built	4th–5th centuries, with later restorations and additions
Built by	Septimius Severus, Constantine I, Constantius II, Theodosius II, Justinian I, Heraclius, Leo V, Theophilos, Manuel I Komnenos
Materials	Limestone, brick
Battles/wars	Avar-Persian siege of 626, First and Second Arab sieges, Revolt of Thomas the Slav, Fourth Crusade, Second and final Ottoman siege
UNESCO World Heritage Site
Type	Cultural
Criteria	i, ii, iii, iv
Designated	1985 (9th session)
Part of	Historic Areas of Istanbul
Reference no.	356
Region	Europe and North America

The Walls of Constantinople (Turkish: Konstantinopolis Surları; Greek: Τείχη της Κωνσταντινουπόλης) are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul in Turkey) 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 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.