Nanchong
5,000 years of continuous silk production along the Jialing River — the longest industrial specialisation in any city on Earth, locked in by mulberry trees, silkworms, and accumulated expertise.
Nanchong has produced silk continuously for five thousand years. Mulberry trees line the Jialing River, silkworms eat the leaves, and 72 silk enterprises employing over 30,000 workers spin the same material that flowed west along the Silk Road from this exact geography in the third millennium BCE. No other industrial specialisation on Earth has persisted this long in one place.
This is path-dependence in its purest form. The mulberry trees grow because the Sichuan Basin's climate sustains them. The silkworms eat the mulberry leaves because that is the only food source the species uses. The expertise accumulates because families have passed silk production techniques through generations. Each element reinforces the others, and the switching costs for any individual component exceed the benefit of changing.
Nanchong has produced silk for 5,000 years — the longest continuous industrial specialisation in any city on Earth, locked in by mulberry trees, silkworms, and accumulated expertise.
The scale is substantial but not dominant. Nanchong's silk industry generates significant revenue, but the city of 5.6 million has diversified into automotive parts, oil and gas (the Sichuan Basin is rich in natural gas), and food processing. The Jialing River connects Nanchong to the Yangtze transport network, giving it logistics access that pure inland cities lack.
Nanchong's historical significance extends beyond silk. Chen Shou, the compiler of the Records of the Three Kingdoms — the foundational text for one of the most important periods in Chinese history — was born here. Zhang Fei, one of the Three Kingdoms' most celebrated generals, served as governor. The city monetises this connection through cultural tourism, though not at the scale of Zunyi's red tourism.
The silk moth analogy is literal rather than metaphorical. Bombyx mori, the domesticated silk moth, has been so thoroughly engineered by 5,000 years of selective breeding that it can no longer fly, find food, or survive in the wild. It exists only because humans maintain its habitat. Nanchong's silk industry operates on the same principle: it persists because the entire support system — trees, worms, workers, equipment — has been co-adapted over millennia into a production chain that cannot be replicated elsewhere and cannot function independently.