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Paul 🌹📚 Cooper @PaulMMCooper
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One of the world’s most incredible ruins is also one of its most mysterious: The ancient Gorgan Wall.

For nearly 1,000 years, this was the longest & mightiest border wall ever built. It was twice as long as Hadrian's Wall, & its construction is an unsolved mystery to this day.
Golestan Province in Northern Iran is a unique landscape.

Between the temperate forests of the Alborz Mountains & the shores of the Caspian Sea, a fertile plain stretches for over 200km, forming a narrow corridor between Persia & the wide desert steppes of Central Asia.
For centuries, this was the northern border of one of the world’s first superpowers: the Sassanian Empire.

The Empire was Persian. It ruled a vast stretch of the Ancient Near East for 400 years, from the 3rd century until its fall to Muslim conquerors in the 7th.
At a time when the Western Roman Empire was collapsing in Europe, the Sassanians flourished.

From its capital in Ctesiphon (south of Baghdad), the empire grew to cover modern Iran & Iraq, stretched into the Caucasus Mountains & even into Pakistan & India.
But the Empire was also menaced by enemies from the north.

The most feared of these were the Hephthalite Empire, the “White Huns”, fierce horseback warriors who had carved out an enormous territory in Central Asia.

(The "Hephthalite bowl", Pakistan, 460–479 CE. @britishmuseum)
Who the White Huns were, what language they spoke & where they came from, is a mystery - but they were feared.

Their swift armies routinely made forays deep into the Sassanian Empire, & the fertile Gorgan region was the main corridor through which they mounted their attacks.
To counter this threat, in the 5th-6th centuries the Sassanians undertook an engineering project of immense ambition.

They began to construct a wall that would stretch the whole length of the Gorgan lowlands, the length of both Hadrian’s Wall & the Antonine Wall put together.
For 1,000 years until the construction of the Great Wall of China, the Gorgan Wall was the longest wall ever built.

So far 195 km (121 mi) of the wall has been discovered, broken by more than 30 fortresses at intervals of 10-50km.

(📷 Georg Gerster)
The Wall of Gorgan was "amongst the most ambitious and sophisticated frontier walls ever built”.

But with no trees or stone in the Gorgan plain, the only building material available was the mud of the river basin itself.

(Ball 2016…)

(📷 Stuart Denison)
Sassanian engineers would need to fire millions of mud bricks for the wall.

To do this, they created an immense mobile brick-making industry. Archaeologists have found remains of kilns built all along the course of the wall, each to an identical blueprint.

(📷 Arman Ershadi)
Mud bricks needed water to be moulded, so as well as building kilns the ancient engineers had to dig 100s of kms of canals to bring water from the rivers to the site of construction, & for workers to drink.

(Nokandeh et al. 2006…)

(📷 Stuart Denison)
Once the wall was completed, these canals were joined up & turned into a moat on the defensive side.

This may also have been used as a water source in the arid plain, & is still visible in the landscape today.
The planning of the wall is evident in its design, with very little variation: it remains 10 meters wide & 3 meters tall almost its entire length.

The wall even crossed rivers, where engineers built dams. Sections are still visible in the silty waters 1,500 years later.
Each brick in the wall is of uniform size & shape (40 x 40 x 10 cm), & the distinctive red colour of the bricks gives it its local name, the “Red Snake” (“Qizil Alan” in Turkeman).

(Chaichian, 2013.…)
To have been effective, the wall must have been constantly garrisoned with a standing army.

Excavations of its barracks suggest that between 15,000 to 36,000 men were stationed in the forts along its length.
Organic material found in the forts shows the Sassanian soldiers consumed a rich diet including fish from the nearby Caspian Sea.

They were supplied & fed by the verdant hinterland of Gorgan, which the wall was built to defend.

(Current Archaeology 2008…)
Despite all this, the Gorgan Wall is still a great mystery. No one knows who ordered it built, or how long it stood for.

“No ancient textual source refers to the Wall, no inscription, and no coin has ever been found on it.”

(Current Archaeology 2008…)
We also don't know why the wall was abandoned & left to crumble.

Around 200 years after its construction, something changed. All activity at the wall suddenly & mysteriously ceased, & it was no longer manned or defended.
Archaeologists speculate that it might have been too expensive to maintain its enormous standing garrison, or the threat of Hunnic raids simply faded.

Perhaps the troops were needed for a war, either dynastic feuding or an attack on the Eastern Roman Empire.

(📷 Stuart Denison)
Today the wall's conservation faces many challenges.

For centuries since its abandonment, people have plundered the wall & used its bricks to furnish their own homes.

(photos by Mohammed Chaichian of houses built using brick taken from the Gorgan Wall…)
The Gorgan Wall has made its mark on legend too, & may have inspired the Iron Gates of Alexander.

It is also associated with the Quranic tale of Dhul Qarnayn (Surat al-Kahf 83-98, who built an enormous iron wall to defend his people against barbarians.
Today, despite the efforts of archaeologists, the Gorgan Wall remains a tantalising mystery.

It reminds us that the history of the world is not the history of the West: that at a time when the order of Western Europe was collapsing, great powers elsewhere were achieving marvels.
Some further reading if you're interested:

- Linear Barriers of Northern Iran:…

- Empires & Walls:…

- Secrets of the Red Snake:…

- Rome in the East:…
Thanks for listening! If you enjoyed this, I’ve gathered more of my research into ruined places here:
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