Theodosian Walls of Constantinople

Timeline

1. 413–439Western land boundary of Constantinople · ConstantinopleUnder Anthemius's direction the empire built an outer moat, low wall, and main wall with 96 towers across the isthmus of the Thracian peninsula, forming an in-depth defense that replaced the old Constantinian walls as the capital's landward line.
2. 1161–1170Constantinople · ConstantinopleIn the mid-12th century the walls remained structurally intact and usable; the empire regularly repaired towers and gates, garrisoning tagma guards and locally levied troops. Though no major siege occurred in this period, the walls' status as the capital's last bulwark was unchanged.