Theodosian Wall (Istanbul Metropolitan Municipality)

In 412 the Roman emperor Theodosius II surrounded Constantinople with a wall that stretched 6.5 kilometers between the Sea of Marmara and the Golden Horn. Although named after Theodosius, they were actually constructed under the direction of Anthemius, Praetorian prefect of the Eastern Empire.

3D reconstruction:
byzantium1200.arkeo3d.com/landwall.html
 byzantineUNESCO World Heritage Sitelisted building / architectural heritagecity wall4th century construction
Wikipedia article: http://en.wikipedia.org/wiki/Walls_of_Theodosius
Nearby cities:
Coordinates:  41°0'51"N 28°55'52"E