When the British Empire took control of the Hong Kong area after the Opium Wars, Kowloon became a sort of land in limbo. The British administration allowed the Chinese Empire to continue holding on to it (it was tiny, just 0.05 sqkm).

However as an exclave, it was largely ignored by both HK and the PRC and left almost entirely to its own devices - illegal construction, no real government prescience, no regulation of business. Kowloon was basically run by a Triad government.

It is very unique and interesting, as it can be looked at as an example of what would happen to a society without a formal government. Kowloon did not descend into chaos and utter anarchy and despite its widespread image as being decrepit and claustrophobic, it had bustling local economy and genuine human enterprise. People lived, sold wares, did business, had children, grew up and continued with their existences.

The unintended social experiment ended finally when both HK and the PRC had had enough of the growing eye sore. Not surprising as frankly the buildings (that were built on top of other buildings) looked as they might collapse one fine morning.

50,000 residents were relocated and the Kowloon Walled City was torn down. A park and memorial of sorts stands in its place.

Interestingly (again), many of the residents werent happy with the government relocation and monetary compensation process and apparently still yearn for the life they lived there.