From the outside, it was 2.7 hectares of fortress. On the inside, it was home to 33,000 people living among rubbish-ridden alleyways and side by side with drugs, prostitution, gambling and rats. Some called it hell on earth, others called it the biggest slum in the world. And in March 1992, it all came down.
The history of the Kowloon Walled City dates from the Sung Dynasty of 960-1297, when it began as a small fort to house the imperial soldiers who controlled the salt trade. In the second half of the 19th century, the Chinese, facing invasion by the British, who held Hong Kong island, expanded it into a proper garrison town containing soldiers, and officials and their families. The walled city became the only part of Hong Kong China was unwilling to cede to Britain under the 99-year lease of Kowloon and the New Territories in 1898. The British agreed that China could keep the city - until the colonial administration for the area was established. But the Chinese never dropped their claim of jurisdiction, and the sovereignty fight remained unresolved - the result being a lawless enclave and a hotbed of criminal activity.
In December 1899, after several unsuccessful attempts to clear the city, the British announced their jurisdiction was to be extended to include it, and the Chinese officials left. The city became isolated, and while parts were leased to church-run, charitable institutions, much was left to fall into disrepair. By 1940 only the Lung Chun School, its gateway and one private home remained. When the Japanese invaded in World War II, they demolished the oldest standing part of the Walled City: its wall, which was used in work on Kai Tak airport.
But the destruction didn't prevent Chinese refugees flocking to the site after the war. Rents were low, and there were no concerns about taxes, visas or licences. By 1947 there were 2,000 squatter camps on the site; permanent buildings followed, and by 1971 10,004 people occupied 2,185 dwellings in what was still referred to as the Walled City. By the late 1980s, it was home to 35,000 people.
The government tried to clear the city several times, but on each occasion the residents threatened to create a diplomatic incident. Their attitude - handy when it came to keeping the authorities' nose out of their business - was that the city was part of China and would never belong to Hong Kong. And to avoid damaging Sino-British relations, the government adopted a largely hands-off policy towards it.
The city again became a hotbed for criminal activity: opium dens, heroin stands, brothels and dog restaurants all multiplied in the '50s and '60s, with police usually turning a blind eye. There were three reasons for that: they were politically hobbled, some were bribed, and it was too dangerous. Real power lay with the triads. But the position changed in the '70s, when a wave of anti-corruption campaigns removed most criminal elements in the authorities. No longer protected, the triads became weaker.