5 longest walls on Earth ranked - and No. 2 is a fortress wall few people know

As we consider the monuments of the past which have become landmarks within our scenery, few pictures come more vividly to mind than those of great stone walls winding their way across the skyline. Such constructions were designed to make an absolute statement in terms of power, security, and eternity. When we picture such ancient barriers in competition with one another, we tend to forget that we are dealing with two different leagues.

When we speak of cities and even whole military fortifications throughout parts of Europe, Asia, and the Middle East, all having been encased by huge stonewalls, there is one particular engineering project from East Asia which stands out because of its scale - literally feeling like an achievement of planetary proportions. There is nothing else like it in the world due to sheer length.

The great scale divide: Continental walls vs city walls

Numbers can only help us appreciate the magnitude of these achievements in terms of scale. Almost all of the long walls that have survived throughout time serve as city or military fort circuits. They were designed as protection for either a localised area of people or an important hilltop location.

According to an official survey documented by the UNESCO World Heritage Convention, the true heavyweights of history are categorised not just by their height, but by the total length of their surviving masonry. When we apply this standard, the gap between the top two spots is so vast that it is nearly impossible to visualise. Here is how the five most significant surviving wall systems on the planet compare.

1. The Great Wall of China

The Great Wall of China stretches through the entire northern region of China and can be considered the most prominent ancient structure for defence. Most people think about only one section of the Great Wall – that constructed during the Ming Dynasty – but in reality, there are trenches, hills, and walls built in different eras. The exact length of the wall, officially measured in China, equals 21,196 km.

2. Kumbhalgarh Fort Wall

Located in the Mewar fortress of Rajasthan, India, this wall is often affectionately called the Great Wall of India. It represents the pinnacle of Rajput military architecture. While it is the clear runner-up globally, its length is approximately 36 kilometres. It is a massive achievement for a single fort, yet it is less than one per cent of the length of the top slot.

3. Diyarbakir Walls

This basalt circuit in Turkey is one of the most important surviving fortified lines in the Near East. Spanning roughly 5.8 kilometres, the walls have stood through the Roman, Byzantine, and Ottoman eras, serving as a dark, imposing reminder of the city's strategic value over thousands of years.

4. The Walls of Ston

Often referred to as the European Great Wall, this 5.5-kilometre limestone barrier in Croatia was built to protect the salt pans of the Republic of Ragusa. It is a striking example of how a relatively small community could mobilise enough resources to wall off an entire peninsula to protect their "white gold."

5. The Walls of Avila

Rounding out the list is Spain’s most complete medieval circuit. Measuring about 2.5 kilometres, these walls feature 88 semi-circular towers and remain so perfectly preserved that they look like a film set. They represent the standard for a perfectly fortified medieval European city.

Why modern measurements keep changing the map

If you feel like the length of the Great Wall has "grown" since you were in school, you are not entirely wrong. The way we measure these ancient giants has evolved significantly with technology. A comprehensive study by the UNESCO World Heritage Convention regarding the Great Wall of China highlights that for centuries, we only counted the standing stone stretches.

Today, researchers use aerial photography and satellite imagery to identify buried sections and natural barriers that were officially part of the defence line. This is why the officially recognised number has jumped from the thousands into the tens of thousands.

In addition, an article in National Geographic gives an explanation for why wall rankings can be defined differently. While some scholars opt to count only the continuous lengths of walls, others consider the total length of the branches. It is due to this reasoning that a fort like Kumbhalgarh can be considered the second-longest continuous wall in the world while being significantly shorter than China’s wall complex.

In essence, these walls represent more than a pile of rocks. They stand as a testimony to the resilience of the human soul. Whether erected for protection for one Spanish town or marking the perimeter of a whole empire, they symbolise the idea that when people choose to erect lasting structures, they alter not just the scenery but also the maps.