1. The Sumerians’ Amorite Wall

Weathered remains of a partially restored ziggurat and the ruins of the city of Ur. (Credit: David Lees/The LIFE Images Collection/Getty Images)
Weathered remains of a partially restored ziggurat and the ruins of the city of Ur. (Credit: David Lees/The LIFE Images Collection/Getty Images)

The world’s earliest known civilization was also one of the first to build a defensive wall. During the 21st century B.C., the ancient Sumerian rulers Shulgi and Shu-Sin constructed a massive fortified barrier to keep out the Amorites, a group of nomadic tribesmen who had been making incursions into Mesopotamia. This “Amorite Wall” is believed to have stretched for over a hundred miles between the Tigris and Euphrates Rivers in what is now Iraq. It was likely the first extensive rampart not built around a city, but it only succeeded in fending off the Sumerians’ enemies for a few years. Hostile invaders either penetrated the wall or simply walked around it, and by the reign of Shu-Sin’s successor, Ibbi-Sin, Sumer found itself under attack from both the Amorites and the neighboring Elamites. After the destruction of the city of Ur around 2000 B.C., Sumerian culture began to vanish from history.

2. The Long Walls of Athens

Map of Athens, including the long walls. (Credit: Public Domain)
Map of Athens, including the long walls. (Credit: Public Domain)

Athens was one of the most powerful cities in ancient Greece, but it was plagued by one major military weakness: it was situated some four miles from the sea. Around 461 B.C., the Athenians sought to correct this vulnerability by constructing a series of barriers to connect the city center to the vital harbors of Piraeus and Phalerum. When completed, these “Long Walls” created a siege-proof triangle of land that allowed the city to easily resupply itself from the sea, which was itself guarded by the mighty Athenian navy. The fortifications made Athens all but impregnable during the Peloponnesian War with Sparta and its allies, but the city was later forced to surrender after its navy was defeated at sea. The victorious Spartans are then said to have dismantled the hated Long Walls to the sound of celebratory music from flute girls. The barriers were later rebuilt, however, and continued to stand until 86 B.C., when they were destroyed by the Roman general Sulla.

3. The Great Wall of Gorgan

Great wall in Gorgan. (Credit: محک/Wiki Commons)
Great wall in Gorgan. (Credit: محک/Wiki Commons)

Also known as the “Red Snake” for its distinctive red-colored bricks, the “Great Wall of Gorgon” was a 121-mile rampart that extended from the southern coast of the Caspian Sea to the Elburz Mountains in what is now Iran. It was once thought to have been the work of Alexander the Great—it was even known as “Alexander’s Barrier”—but more recent research suggests it was built by the Sasanian Persians sometime around the 5th century A.D. When completed, it was one of the longest walls of antiquity and boasted more than 30 forts, a garrison of 30,000 troops and a network of canals that acted as both a water supply system and a defensive moat. Surprisingly little is known about the wall’s history, but most scholars believe the Persians used it to guard against the Hephthalite Huns and other enemies to the north.

4. Hadrian’s Wall

Photo of modern ruins of Hadrian’s Wall. (DEA/S. VANNINI/Getty Images)
Photo of modern ruins of Hadrian’s Wall. (DEA/S. VANNINI/Getty Images)

Around 122 A.D., the Emperor Hadrian ordered the construction of a stone barrier to protect Roman Britain from the Picts and the other “barbarian” tribes that inhabited northern England and Scotland. The result was “Hadrian’s Wall,” a 73-mile rampart that stretched from the Solway Firth on the western coast to the mouth of the River Tyne in the east. The wall was roughly 10 feet wide and 15 feet tall and was dotted with forts manned by frontier troops. Gates spaced one mile apart allowed the garrison to control movement in the region—the wall may have even been used to levy taxes—and defensive towers and ditches protected against raids from the north. Though briefly decommissioned in the 140s in favor of a more northerly barrier called the Antonine Wall, Hadrian’s Wall was later reoccupied and remained an imposing symbol of Roman power until their withdrawal from Britain in the early 5th century. 1,600 years of deterioration and looting for building materials have since reduced it to a fraction of its original size, but many portions still exist today and are among England’s most visited historical sites.

5. The Great Wall of China

A general view shows part of the Great Wall.  (Credit: ChinaFotoPress/ChinaFotoPress/Getty Images)
A general view shows part of the Great Wall. (Credit: ChinaFotoPress/ChinaFotoPress/Getty Images)

Rather than a single unbroken barrier, China’s legendary Great Wall is actually a collection of stone, wood and earthen barricades that meander for thousands of miles from the Gobi Desert to the North Korean border. Construction on the fortifications began in the 3rd century B.C. under Emperor Qin Shi Huang, but the most famous sections were erected between the 14th and 17th centuries A.D. to defend the Ming Dynasty against the steppe nomads to the north. These portions stand up to 25 feet tall and were built using bricks and a mortar made from slaked lime and sticky rice. Gates were positioned along key strongpoints and trade routes, and watchtowers were used to send smoke and fire signals in the event of an attack. The completed wall was once the largest manmade object in the world, but despite its grandeur, it often proved ineffective as a defensive barrier. The Mongol leader Altan Khan famously bypassed the wall and raided Beijing in 1550, and the Manchus later broke through in 1644 and brought about the fall of the Ming Dynasty.

6. The Walls of Constantinople

The Theodosian city walls originally built in the 5th century during reign of Theodosius II. (Credit: Ken Welsh/Getty Images)
The Theodosian city walls originally built in the 5th century during reign of Theodosius II. (Credit: Ken Welsh/Getty Images)

The Byzantine metropolis of Constantinople (modern day Istanbul) flourished for over a millennium thanks in part to the strength of its defensive walls. More than 14 miles of barricades surrounded the city, but the most famous were the Theodosian Walls, which blocked armies from advancing from the mainland. They included a moat, a 27-foot outer wall and a massive inner wall that was 40 feet tall and 15 feet thick. Troops stood guard on the ramparts at all times, ready to rain arrows and a type of ancient napalm called “Greek fire” on any enemy that dared attack them. The walls succeeded in turning back a host of would-be conquerors from the Arabs to Attila the Hun, but they finally met their match in 1453, when the Ottoman Empire besieged the city with a frightening new weapon—the cannon. After using their artillery to blast holes in the walls, the Turks poured through the breach and captured Constantinople, effectively toppling the Byzantine Empire.

7. The Berlin Wall

Berlin wall. (Credit: spreephoto.de/Getty Images)
Berlin wall. (Credit: spreephoto.de/Getty Images)

Modern history’s most infamous wall was erected in 1961, when the Soviet-aligned East German government built a series of concrete partitions separating East and West Berlin. While Communist leaders claimed the barriers were designed to keep out fascists and other enemies of the state, their real function was to prevent East Germans from defecting to the West. More than 100 people were eventually killed while trying to escape through the maze of 12-foot walls, guard towers and electrified fences. Thousands more succeeded by scaling the wall, tunneling underneath it and even flying over it in ultra-light aircraft and homemade hot air balloons. Despite the Berlin Wall’s notorious reputation—Westerners dubbed it the “Wall of Shame”—it stood for more than 28 years before East German authorities finally opened it on November 9, 1989. The announcement sparked a wave of celebrations, and elated Berliners soon went to work demolishing the wall with jackhammers and chisels. East and West Germany were officially reunified less than a year later in October 1990.