World's most renowned walls

Saksaywaman is a citadel on the northern outskirts of the city of Cusco, Peru, the historic capital of the Inca Empire. Sections were first built by the Killke culture about 1100; they had occupied the area since 900. The complex was expanded and added to by the Inca from the 13th century; they built dry stone walls constructed of huge stones. The workers carefully cut the boulders to fit them together tightly without mortar. The site is at an altitude of 3,701 m (12,142 ft).

 

Hadrian's Wall was a defensive fortification in the Roman province of Britannia, begun in 122 AD in the reign of the emperor Hadrian. It ran from the banks of the River Tyne near the North Sea to the Solway Firth on the Irish Sea, and was the northern limit of the Roman Empire, immediately north of which were the lands of the northern Ancient Britons, including the Picts. It had a stone base and a stone wall. There were milecastles with two turrets in between. There was a fort about every five Roman miles. From north to south, the wall comprised a ditch, wall, military way and vallum, another ditch with adjoining mounds. It is thought the milecastles were staffed with static garrisons, whereas the forts had fighting garrisons of infantry and cavalry 

The Western Wall, Wailing Wall or Kotel  is an ancient limestone wall in the Old City of Jerusalem. It is a relatively small segment of a far longer ancient retaining wall, known also in its entirety as the "Western Wall". The wall was originally erected as part of the expansion of the Second Jewish Temple by Herod the Great, which resulted in the encasement of the natural, steep hill known to Jews and Christians as the Temple Mount, in a large rectangular structure topped by a huge flat platform, thus creating more space for the Temple itself and its auxiliary buildings

The Walls of Constantinople 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.

The Great Wall of China is a series of fortifications made of stone, brick, tamped earth, wood, and other materials, generally built along an east-to-west line across the historical northern borders of China to protect the Chinese states and empires against the raids and invasions of the various nomadic groups of the Eurasian Steppe. Several walls were being built as early as the 7th century BC; these, later joined together and made bigger and stronger, are now collectively referred to as the Great Wall. Especially famous is the wall built 220-206 BC by Qin Shi Huang, the first Emperor of China. Little of that wall remains. Since then, the Great Wall has been rebuilt, maintained, and enhanced; the majority of the existing wall is from the Ming Dynasty (1368-1644)

The Aurelian Walls are a line of city walls built between 271 AD and 275 AD in Rome, Italy, during the reign of the Roman Emperors Aurelian and Probus. They superseded the earlier Servian Wall built during the 4th century BC. The walls enclosed all the seven hills of Rome plus the Campus Martius and, on the right bank of the Tiber, the Trastevere district. The river banks within the city limits appear to have been left unfortified, although they were fortified along the Campus Martius. The size of the entire enclosed area is 1,400 hectares (3,500 acres)

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