Seoul
Han River's defensible valley became capital for three Korean dynasties—state-directed chaebol capitalism turned Seoul into a 26-million megacity generating half of Korean GDP. 2026: birth rates and artillery range test centralization.
Seoul exists because the Han River offered both defense and commerce—a wide valley protected by mountains on three sides, navigable to the Yellow Sea, positioned at the center of the Korean peninsula. That geographic centrality made Seoul the capital of three successive Korean states and the command center for one of history's most compressed industrializations.
In 1394, the Joseon dynasty moved Korea's capital from Kaesong to Hanyang (Seoul), building Gyeongbokgung Palace and a city wall following feng shui principles. For 500 years, Seoul remained a compact administrative center of 200,000. Japanese colonization (1910-1945) brought modern infrastructure but also cultural suppression. The Korean War destroyed 80% of the city. In 1953, Seoul had 1 million residents and no industry.
What followed was the 'Miracle on the Han.' Park Chung-hee's state-directed capitalism channeled resources through chaebol (family conglomerates). Samsung, LG, Hyundai, and SK built their headquarters in Seoul. By 1990, the population reached 10 million; today the Seoul Capital Area holds 26 million—half of South Korea. The city generates 21% of national GDP through finance, technology, and headquarters functions. Samsung alone contributes 15% of Korean exports. K-pop and Korean drama production concentrate in Gangnam studios. Seoul ranks among Asia's five largest financial centers.
The 2026 trajectory reveals Seoul's structural vulnerabilities. North Korean artillery can reach the capital in minutes—the DMZ lies 35 kilometers away. The city's low birth rate (0.55 children per woman—lowest on Earth) accelerates population decline. Housing prices doubled 2017-2021, pricing out young families. Yet Seoul bets on AI (Samsung's $15 billion semiconductor investment), biotechnology (clustered in Pangyo Techno Valley), and cultural exports that make 'Hallyu' a $12 billion industry. The same geographic centrality that made Seoul inevitable for 600 years now makes decentralization impossible—path dependence at peninsula scale.