What defensive land wall protected Constantinople from enemy attacks?

What defensive land wall protected Constantinople from enemy attacks? The answer is the Theodosian Walls. This massive double line of fortifications defended Constantinople’s western landward side, where the city was most vulnerable. The walls were named after Emperor Theodosius II, during whose reign the main system was constructed and expanded.

The first phase was completed in 413 under the supervision of the praetorian prefect Anthemius. After a major earthquake in 447 damaged the defenses, the city rapidly rebuilt and strengthened them. The finished system included a high inner wall, a lower outer wall, broad terraces, towers, and a moat. It extended for roughly 5.7 kilometers from the Sea of Marmara toward the Golden Horn.

The fortifications helped Constantinople withstand repeated attacks by Avars, Persians, Arabs, Rus’, Bulgars, and others. They were not the same as Hadrian’s Wall or Rome’s Aurelian Walls, which protected different places. The Theodosian Walls remained formidable even during the Ottoman siege of 1453, although artillery, prolonged pressure, and the city’s limited manpower eventually contributed to Constantinople’s fall.