1. Kowloon Walled City (Hong Kong)
Before its demolition in 1993, Kowloon Walled City was infamous for its maze-like infrastructure, rampant crime, and lack of any formal regulation. Home to over 30,000 residents on just 6.4 acres, it embodied urban anarchy and resourcefulness. Its population density surpassed that of any modern city, and its legacy remains a symbol of both resilience and neglect. (nationalgeographic.com)
