I came across a video on Youtube discussing it (there are several), and Kowloon Walled City is just endlessly fascinating. A few notable videos I found on the subject were:
Kowloon Walled City: Hong Kong’s City of Darkness
Inside Hong Kong’s Kowloon Walled City
There is also a book on the city called City Of Darkness Life In Kowloon Walled City, which I found on archive.org in high resolution. It is full of photographs and detailed accounts of the comings and goings within the enclave.
Pretty much the entire game of Shadowrun: Hong Kong revolves around Kowloon Walled city and it’s one of my favourite games.
Goddamn, I played and loved the first two Shadowruns by Harebrained, and then left Hong Kong at the start due to lack of time. Reading this makes me want to puck it up immediately!
It’s definitely my favourite of the 3.