九龍寨城 Kowloon walled city

Kowloon Walled City was a densely populated, largely ungoverned settlement in Kowloon, Hong Kong. It was a military fort for hundreds of years, but later became a very dense settlement. In 1980, the city had about 35,000 people on about 20,000 m² of land, making it one of the most densely populated places on earth. From the 1950s to the 1970s, it was controlled by Triads (Chinese gangsters) and had high rates of prostitution, gambling, and drug use. 

Kowloon Walled City was torn down in 1993, and a park called Kowloon Walled City Park was built in 1994. 

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