Hong Kong (香港; "Fragrant Harbour"), officially Hong Kong Special Administrative Region of the People's Republic of China, is an autonomous territory on the southern coast of China at the Pearl River Estuary and the South China Sea. Hong Kong is known for its skyline and deep natural harbour. It has a land area of 1104 km2 and shares its northern border with Guangdong Province of Mainland China. With around 7.2 million inhabitants of various nationalities, Hong Kong is one of the world's most densely populated metropolises.
After the First Opium War (1839–42), Hong Kong became a British colony with the perpetual cession of Hong Kong Island, followed by Kowloon Peninsula in 1860 and a 99-year lease of the New Territories from 1898. Hong Kong remained under British control for about a century until the Second World War, when Japan occupied the colony from December 1941 to August 1945. After the Surrender of Japan, the British resumed control. In the 1980s, negotiations between the United Kingdom and the China resulted in the 1984 Sino-British Joint Declaration, which provided for the transfer of sovereignty of Hong Kong on 30 June 1997. The territory became a special administrative region of China with a high degree of autonomy on 1 July 1997 under the principle of one country, two systems. Disputes over the perceived misapplication of this principle have contributed to popular protests, including the 2014 Umbrella Revolution.