Macau, also spelled Macao and officially the Macao Special Administrative Region of the People's Republic of China, is an autonomous territory on the western side of the Pearl River estuary in East Asia. Macau is bordered by the city of Zhuhai in Mainland China to the north and the Pearl River Delta to the east and south. Hong Kong lies about 64 kilometres to its east across the Delta. With a population of 650,900 living in an area of 30.5 km², it is the most densely populated region in the world. A former Portuguese colony, it was returned to Chinese sovereignty on 20 December 1999.
Macau is a resort city in Southern China, known for its casinos and luxury hotels. Its gaming revenue has been the world's largest since 2006, with the economy heavily dependent on gaming and tourism. According to The World Factbook, Macau has the fourth highest life expectancy in the world. Moreover, it has a very high Human Development Index, ranking 17th in the world as of 2016. Macau is among the world's richest regions and its GDP per capita by purchasing power parity was higher than that of any country in the world, according to the World Bank.
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