How Long Is The Great Wall of China? The Truth Will Amaze You

The Great Wall of China

The true length of the Great Wall of China might surprise many who think they know this ancient wonder's dimensions. Recent studies have revealed that the Great Wall extends 21,196.18 kilometers (13,170.70 miles), which is nowhere near the previously estimated 6,700 kilometers.

This remarkable series of fortifications took shape over 2,500 years, from the 7th century BC to 1878. The Great Wall isn't a single continuous structure but rather an impressive network of walls, towers, and garrison stations that spans 15 northern Chinese provinces. The Ming Dynasty sections remain the best preserved today, stretching 8,851.8 kilometers of this architectural marvel.

Let's explore the actual dimensions of the Great Wall and discover how its length changed through various dynasties. We'll also delve into the unique challenges that come with measuring this UNESCO World Heritage Site.

The Official Length of the Great Wall

Chinese archeologists have finally shown the true length of this architectural marvel after years of guessing and different estimates. A detailed five-year archeological survey completed in 2012 led the National Cultural Heritage Administration to announce that the Great Wall stretches 21,196.18 kilometers (13,170.70 miles).

Total length in kilometers and miles

The complete measurement includes all known sections built during different dynasties that stretch across 15 provinces and regions. The survey team found 43,721 distinct relics that include walls, trenches, towers, and fortresses. The total length equals about half of Earth's equator's circumference.

Length of well-preserved sections

The Ming Dynasty (1368-1644) built the best-preserved parts of the Great Wall. These sections run for 8,851.8 kilometers (5,500.3 miles) and consist of:

• 6,259.6 kilometers of artificial walls
• 359.7 kilometers of trenches
• 2,232.5 kilometers of natural barriers

Only 9.4% of the original wall stands intact today. The prominent sections like Badaling and Mutianyu make up just a small part of the whole structure.

How the length was measured

The measurement project stands out as the most detailed effort ever attempted. It brought together 1,295 professionals from the State Administration of Cultural Heritage and the State Bureau of Surveying and Mapping. The team used both old and new methods:

1. Traditional tools:

   • Compass
   • Tape measure
   • Spirit level

2. Advanced technology:

   • Electronic distance measurement (EDM)
   • GPS systems
   • Satellite mapping

The survey team walked more than 100,000 kilometers - the same as walking every trail in Switzerland. They collected 46,111 data forms, 200,000 photographs, and 30,000 videos during their journey.

New sections keep adding to the Wall's documented length. Recent findings show:

• A 40-kilometer Ming Wall section in Tianjin (2012)
• A 46.585-kilometer Western Han Dynasty segment in Inner Mongolia (2014)
• Multiple Qin Dynasty sections along the Ningxia-Gansu border (2015)
• A 4-kilometer section in Liangcheng County (2017)

These ongoing discoveries highlight the Wall's massive scale and historical importance. Future surveys might reveal even longer lengths. This measurement project helps us understand this ancient fortification system better than ever before.

How the Wall's Length Changed Over Time

China's most ambitious architectural project took more than two thousand years to build. The story begins in the 7th century BCE, when separate fortifications grew into an interconnected defensive marvel that would shape China's history.

Original wall segments

The first walls appeared as standalone fortifications during the Spring and Autumn period (771-476 BCE). Different kingdoms built these defensive structures until a defining moment changed everything.

Emperor Qin Shi Huang unified China around 221-206 BCE. He ordered workers to tear down internal fortifications between states and connect the northern walls into one defensive system. This massive project became known as the "10,000-Li Long Wall." Workers completed this task in about ten years, starting around 214 BCE.

Major expansions by dynasty

Each dynasty left its unique mark on the Wall:

• Han Dynasty (202 BCE - 220 CE)

  • Pushed fortifications westward into the Gobi Desert
  • Added signal towers to improve communication
  • Brought stone construction to specific areas

• Northern Wei Dynasty (386-534 CE)

  • Fixed existing sections
  • Built new fortifications against Juan-juan and Khitan tribes
  • Created the Six Frontier Towns

• Sui Dynasty (581-618)

  • Completed seven major repair projects
  • Put over a million workers to work on construction

• Ming Dynasty (1368-1644)

  • Launched the largest rebuilding program
  • Rebuilt walls with brick and stone
  • Added beacon towers and garrison stations
  • Created 8,850 kilometers of fortifications

The Ming Dynasty created the Wall's most sophisticated version. Their work included 6,259 kilometers of wall sections, 359 kilometers of trenches, and 2,232 kilometers of natural defensive barriers.

The Wall's growth matched changing military needs. Builders first designed it to protect unified China from Xiongnu tribes, but it later protected vital Silk Road trade routes. The Wall served many purposes through time - it controlled trade and immigration and showed imperial power.

The final major construction phase transformed simple earthen ramparts into an intricate defensive network. Ming Dynasty builders used advanced techniques and strategic planning to create the iconic structure we see today, complete with watchtowers, garrison stations, and signaling platforms.

Different Types of Wall Sections

"The Great Wall reflects collision and exchanges between agricultural civilizations and nomadic civilizations in ancient China. It provides significant physical evidence of the far-sighted political strategic thinking and mighty military and national defense forces of central empires in ancient China, and is an outstanding example of the superb military architecture, technology and art of ancient China." — UNESCO World Heritage Committee, United Nations Educational, Scientific and Cultural Organization

The Great Wall's architectural diversity reveals how ancient Chinese engineers mastered different construction methods and materials. Each section of this magnificent structure tells its own story of adaptation and state-of-the-art building techniques, from basic natural barriers to complex fortifications.

Mountain ridges and natural barriers

Natural defensive barriers make up one-fourth of the Wall's total length. Chinese builders cleverly used mountain ridges, rivers, and steep cliffs as part of the Wall's design to maximize defensive capabilities. The Hexi Corridor stands out with its impressive 5,000-kilometer span that uses high mountains, steep cliffs, and wide rivers in its defensive network.

Brick and stone fortifications

The Ming Dynasty brought a fundamental change toward stronger building materials. Ming wall sections were built 21.3 feet wide at the base and narrowed to 19 feet at the top, with heights between 23 and 26 feet. These sections had advanced defensive features:

• Stone foundations that supported brick upper structures
• Arched doorways (juan) with internal staircases
• Crenelated platforms placed 650-1,000 feet apart
• Drainage systems that prevented water damage

Stone became the preferred material in areas needing extra durability because it resisted weathering better. Expert craftsmen carefully placed each stone to create interlocking structures that spread weight evenly across the wall.

Earthen ramparts

Rammed earth was the main construction technique before bricks became accessible to more people. Builders followed these steps:

1. Created wooden frames
2. Filled them with earth, gravel, and lime
3. Compressed the materials into solid layers

Desert region builders showed remarkable creativity by mixing native desert plants, especially tamarisk, with gravel to create surprisingly strong materials. The Qi wall that stretched to the Yellow Sea shores became a prime example of this earth-and-stone building method.

The Bei Qi period saw extensive earthen wall construction, adding approximately 900 miles of new sections along the Taihang Mountains. These sections included periodic towns and barracks that created a detailed defensive network. Some Sui Dynasty earthen ramparts still stand in Inner Mongolia today, reaching 2.5 meters high with towers twice that height.

Local terrain and available materials determined the wall's construction methods. Stone was the main material in mountainous areas, while builders used bricks and tamped earth in plains and deserts. This flexibility helped the wall work effectively across China's varied landscape and created a defensive system complete with fortresses, beacon towers, and troop barracks.

Measuring Challenges and Methods

Scientists have struggled for centuries to determine the exact length of the Great Wall. A complete five-year archeological survey in 2012 marked a significant step toward measuring this ancient marvel accurately.

Traditional measurement techniques

Chinese surveyors from ancient times used sophisticated mathematical principles and simple tools to measure Wall segments. Their tools included:

• Sighting poles (gnomons)
• Set squares and plumb lines
• Water levels and measuring ropes
• Mathematical aids like the Haidao Suanjing

These surveyors worked with six key principles to map accurately:

1. Appropriate scale usage
2. Rectangular grid system implementation
3. Precise landmark measurements
4. Elevation determination
5. Angle measurements
6. Curve and line assessments

Modern satellite mapping

Today's measurement efforts blend traditional methods with state-of-the-art tools. The State Administration of Cultural Heritage and State Bureau of Surveying and Mapping used:

• Electronic distance measurement (EDM) devices
• GPS technology
• Advanced mapping software
• Infrared range finders

The measurement team of 1,295 professionals walked more than 100,000 kilometers - equal to every trail in Switzerland. Their detailed work generated:

• 46,111 data forms
• 200,000 photographs
• 30,000 videos
• Documentation of 43,721 distinct relics

Ongoing length verification

The Wall's measurement continues as an active process because:

1. New sections keep emerging:

   • Scientists found a 40-kilometer Ming Wall section in Tianjin (2012)
   • A 46.585-kilometer Western Han Dynasty segment appeared in Inner Mongolia (2014)
   • Teams identified multiple Qin Dynasty sections along the Ningxia-Gansu border (2015)
   • Researchers uncovered a 4-kilometer section in Liangcheng County (2017)

2. Natural and human factors change measurements:

   • Wind erosion and rainfall wear down wall integrity
   • Freeze-thaw cycles alter structural features
   • Only 5.8% of the total length stays well-preserved
   • 52.4% has disappeared or severely deteriorated

Modern techniques have achieved remarkable accuracy. The Badaling section test (about 2.5 kilometers) showed a plane mean square error of 5.0 meters and an elevation mean square error of 2.0 meters. These parameters suggest an expected measurement accuracy of ±0.866 kilometers for the entire Wall.

Biocrusts serve a significant role in wall preservation. Defense districts with the highest total stability show 11.2% to 62.5% higher preservation rates than others. This knowledge helps researchers track structural changes when they verify measurements over time.

Geographic Spread Across China

The Great Wall snakes through northern China in an impressive arc that marks where the Mongolian steppe begins. This architectural wonder runs through ten provinces, autonomous regions, and municipalities, which created a defensive network that shaped China's northern frontier.

Eastern starting point

Hushan Mountain in Liaoning Province marks the Great Wall's eastern end, with coordinates at 124°30'50"E, 40°13'19"N. People once thought Shanhaiguan Pass was the eastern endpoint. Archeological findings in the 1980s changed this view when researchers found ancient walls near Hushan Mountain in Dandong City. These discoveries showed the Hushan Great Wall stretches more than 1,000 kilometers east of Shanhaiguan.

Western terminus

The mighty Jiayu Pass in Gansu province stands at the opposite end and marks the Wall's western frontier. This strategic fortress sits between two hills at the Hexi Corridor's narrowest point and is a vital waypoint on the ancient Silk Road. The pass earned its name "Last Pass Under Heaven" and lies 6 kilometers southwest of Jiayuguan city.

Near Jiayu Pass, the First Fire Tower represents the westernmost pier of the Ming Great Wall. Today, only an earthen base about 10 meters high remains of this historic structure that played a key role in military surveillance and communication. The surrounding views paint a dramatic picture:

• The Gobi Desert stretches endlessly west
• Jiayuguan City rises proudly north
• The Qilian Mountains dominate the southern horizon
• The Taolai River flows peacefully at its base

The Wall's path covers 156 counties through provinces including:

• Liaoning
• Hebei
• Tianjin
• Beijing
• Shanxi
• Inner Mongolia
• Shaanxi
• Ningxia
• Gansu
• Qinghai

This remarkable fortification shows how ancient Chinese engineers adapted their building methods to different landscapes. The Wall stands as proof of human determination and architectural brilliance, stretching from the Bohai Sea's coastal regions to western China's desert landscapes.

Conclusion

Chinese engineering and determination produced a defensive marvel that stretches an incredible 21,196.18 kilometers through a variety of landscapes. This architectural achievement took 2,500 years and multiple dynasties to build, showing evidence of human perseverance and innovation.

New findings keep adding to our knowledge of the Wall's actual size. Modern measurement techniques help archeologists find new sections, even though all but one of these sections have crumbled away. These discoveries hint at the possibility of the wall being even longer than we know today.

The Great Wall means much more than a defensive barrier. Every stone, brick, and earthen rampart reveals stories about ancient Chinese civilization. The wall showcases remarkable building methods adapted to different terrains. This UNESCO World Heritage site proves exceptional engineering skills, stretching from the Bohai Sea's coastal areas to western China's harsh deserts.

Scientists and archeologists work hard to protect and examine this remarkable structure for future generations. Their work, along with modern technology, helps us understand this extraordinary achievement that shaped ancient China's northern frontier.

FAQs

Q1. How long is the Great Wall of China? The Great Wall of China stretches an impressive 21,196.18 kilometers (13,170.70 miles), which is about half the circumference of the Earth at the equator. This total length includes all known sections built across various dynasties.

Q2. How long does it take to walk the entire Great Wall? Walking the entire length of the Great Wall would theoretically take around 18 months or longer. However, hiking just the well-preserved Ming Dynasty section (8,851.8 kilometers) would take approximately 3-5 months.

Q3. What are the main types of wall sections? The Great Wall consists of three main types of sections: natural barriers like mountain ridges and rivers, brick and stone fortifications (particularly from the Ming Dynasty), and earthen ramparts made of rammed earth and local materials.

Q4. How was the length of the Great Wall measured? The length was determined through a comprehensive five-year archeological survey completed in 2012. The team used a combination of traditional tools and modern technology, including GPS systems, satellite mapping, and on-foot exploration, covering over 100,000 kilometers.

Q5. Where does the Great Wall begin and end? The eastern starting point of the Great Wall is at Hushan Mountain in Liaoning Province, while the western terminus is marked by the Jiayu Pass in Gansu Province. The wall spans across 15 provinces, autonomous regions, and municipalities in northern China.