China's Great Wall, built and rebuilt across multiple dynasties from roughly the 7th century BCE to the 17th century CE, totals approximately 21,196 km when every wall, trench, and natural defensive barrier from all its branches is included, per a comprehensive 2012 survey by China's State Administration of Cultural Heritage — the longest wall ever built by a wide margin.
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China's Great Wall, built and rebuilt across multiple dynasties from roughly the 7th century BCE to the 17th century CE, totals approximately 21,196 km when every wall, trench, and natural defensive barrier from all its branches is included, per a comprehensive 2012 survey by China's State Administration of Cultural Heritage — the longest wall ever built by a wide margin.
The greatest total length of any human-built wall structure, including all branches and sections built across different historical periods.
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Permanent ID limitsregistry.com/limits/LR-LONGEST-WALL
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Limits Registry. LR-LONGEST-WALL. Longest wall ever built. 2026.