Anastasian Wall
Thrace, Turkey · built 460
The Anastasian Wall (Ἀ ῖ, Anastáseion Teîchos, Anastasius Suru) or the Long Walls of Thrace (ὰ ῆ, Makrà Teíchē tês Thrákēs) or simply the Long Wall (ὸ ῖ, Uzun Duvar) is an ancient stone and turf fortification located 64 km (40 mi) west of Constantinople, built by the Eastern Roman Empire during the late 5th century.
Archaeological site data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).