The Kowloon Walled City Park is one of the oldest and most significant historic sites in the territory, used by imperial officials in the 15th century and later fortified in 1668. Around 1810, a small fort was added and later a wall garrison city was constructed to shore up maritime defences of China, following the British occupation of Hong Kong Island, and massive stone walls with six watchtowers and four gates enclosed the area. The Kowloon Walled City Park went through a fascinating history through the war, after which high rise tenements mushroomed on the site, and the walled city became a haven for drug dealers, criminal hide-outs, vice dens and even cheap, unlicensed dentists. The decision was taken by the Chinese authorities to build the area into a park, and during clearing many relics were unearthed and incorporate into the design or preserved as exhibits. Today the Kowloon Walled City Park covers 31,000 square metres, and is divided into 8 scenic zones.