Limits RegistryPUBLIC RECORD
Limits RegistryXianren Bridge (Fairy Bridge), in Guangxi, China, has a span of approximately 400 m — the longest known natural arch in the world, formed by water erosion through limestone karst terrain over thousands of years.
The question, scope, and sources behind this Registry record.
Xianren Bridge (Fairy Bridge), in Guangxi, China, has a span of approximately 400 m — the longest known natural arch in the world, formed by water erosion through limestone karst terrain over thousands of years.
The greatest span length of any known natural rock arch.
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Permanent ID limitsregistry.com/limits/LR-LONGEST-NATURAL-ARCH
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Limits Registry. LR-LONGEST-NATURAL-ARCH. Longest natural arch. 2026.