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The Chinese Navy is building a string of overseas bases. So far the largest and furthest afield is in Djibouti on the Horn of Africa. This strategically-located base appears ready to receive large warships, maybe even aircraft carriers. One aspect of the base is particularly interesting: It is a modern-day fortress built from scratch. If the Communist country was hoping to give off non-imperialist vibes as it expands its presence overseas, then it may have chosen the wrong architects.

And it is not just castle aesthetics, the base really is designed to be highly defendable on a scale rarely seen, even in war zones. Construction of the walls started in early 2016, and was substantially complete by spring 2017. The base has been built up since.

Approaching by road, you first have to turn off the perimeter road and pass through a substantial automated outer gate. Turning 90 degrees, always good for slowing vehicles down, you then pass through two vehicle checkpoints and a chicane. Eventually the main gate is in sight. It appears to have last-ditch pop-up vehicle barriers and large concrete doors.

Inside the Hesco wall is the main wall built out of concrete. It has crenelations, meaning the up-and-down style battlements familiar from medieval castles. There are also gun loops, which are holes to fire weapons through. And there are tall towers on the corners.

Not every side of the base is defended equally, but there are substantial defenses on all sides. Even approaching from the water side of the base would require negotiating a series of security fences and guard positions. Inside the base itself there are a few more defensive positions.

An attack on the base would be responded to by the marines stationed there. Armored vehicles seen in the base include ZBD-09 infantry fighting vehicles and ZTL-11 assault guns. These are armed with an array of automatic cannons, anti-tank missiles and large caliber guns.

Other countries’ military bases in Djibouti, such as the U.S. Navy’s Expeditionary Base at Camp Lemonnier, also have physical defenses, but nothing that compares to the Chinese base.

So who are they defending against? This style of defenses are negligible against advanced adversaries. So it appears that the focus is on insurgents and local low-tech threats.

China does not have first hand experience of its bases being attacked in the way that Western forces have in Afghanistan and Iraq. But it may have learned from them. Yet it is hard not to see these defenses and draw parallels with ancient Chinese forts and of course the Great Wall of China