Once home to fishermen and farmers, modern Hong Kong is a teeming, commercially-vibrant metropolis where Chinese and Western influences fuse.
The former British colony became a special administrative region of China in 1997, when Britain's 99-year lease of the New Territories, north of Hong Kong island, expired.
Hong Kong is governed under the principle of "one country, two systems", under which China has agreed to give the region a high degree of autonomy and to preserve its economic and social systems for 50 years from the date of the handover.
But Beijing can veto changes to the political system, and pro-democracy forces have been frustrated by what they see as the slow pace of political reform.
Electoral reform is a particularly sore point. Currently, half the territory's legislature is not directly elected, but chosen by professional and corporate groups that favour Beijing loyalists.
The territory's chief executive is indirectly elected by an electoral college effectively controlled by Beijing.
China has pledged to allow the chief executive to be elected by direct universal adult suffrage by 2017, but wants all candidates to be chosen by a nominating committee.
Pro-democracy activists say the public should be involved in deciding who can stand. Beijing worries this could undermine its control over the territory.
Tensions spilled over into mass protests in the city centre in September 2014, with calls for full democracy and the resignation of Chief Executive CY Leung, and the territory's Legislative Council rejected the proposed changes the following year.
China controls Hong Kong's foreign and defence policies, but the territory has its own currency and customs status.
Hong Kong's economy has moved away from manufacturing and is now services-based. The region is a major corporate and banking centre as well as a conduit for China's burgeoning exports. Its deepwater port is one of the world's busiest.
Companies based in Hong Kong employ millions of workers in the neighbouring Chinese province of Guangdong.
China ceded Hong Kong island to Britain in 1842 after the First Opium War. Britain later added parts of the Kowloon peninsula and the many smaller islands surrounding Hong Kong to its holdings.
In the 19th and 20th centuries Hong Kong's population was boosted by the arrival of hundreds of thousands of migrants from China, many of whom were fleeing domestic upheavals.
Industrialisation gathered pace, and by the 1970s Hong Kong had become an "Asian tiger"; one of the region's economic powerhouses.
With little room for expansion across its hilly terrain, high-rise Hong Kong has among the highest population density in the world - about 6,300 people per square kilometre.
Skyscrapers and temples, shopping malls and traditional markets sit cheek-by-jowl. But amid the urban hustle there are quiet parks and green spaces, beaches and mountain-top views.