Hong Kong occupies 1,106 square kilometers on the southeastern coast of China at the mouth of the Pearl River Delta. The territory comprises Hong Kong Island, the Kowloon Peninsula, the New Territories, and 263 outlying islands. The border with Guangdong Province runs 33 kilometers along the northern edge of the New Territories. Victoria Harbour separates Hong Kong Island from Kowloon Peninsula, forming a natural deepwater channel averaging 1.2 kilometers wide. The harbor reaches depths of 12 meters in shipping channels, a geological feature that determined Hong Kong's function as a port. Hong Kong Island covers 80.4 square kilometers. Kowloon Peninsula adds 46.9 square kilometers. The New Territories account for 748 square kilometers, approximately 68 percent of total land area. Lantau Island measures 147.2 square kilometers, making it the largest of the outlying islands.
Tai Mo Shan rises 957 meters above sea level in the central New Territories, the highest point in Hong Kong. Victoria Peak reaches 552 meters on Hong Kong Island. Lion Rock, a granite formation in the mountain range separating Kowloon from the New Territories, stands 495 meters high. Sunset Peak on Lantau Island measures 869 meters. Sharp Peak in the Sai Kung Peninsula rises to 468 meters. These elevations create terrain where 75 percent of Hong Kong's land area has slopes exceeding 15 degrees. Flat land suitable for development represents approximately 25 percent of total area, concentrated along coastlines and reclaimed zones. The mountainous topography confines urban development to narrow coastal strips and valley floors.
Hong Kong sits on Mesozoic granite and volcanic rocks formed 140 to 165 million years ago during the Jurassic and Cretaceous periods. The Hong Kong UNESCO Global Geopark, established in 2009 and expanded in 2011, preserves 150 square kilometers of geological formations across the Sai Kung Volcanic Rock Region and the Northeast New Territories Sedimentary Rock Region. Hexagonal volcanic rock columns on Sharp Island and the northeastern coast formed when rhyolitic lava cooled 140 million years ago. Some columns measure 1.2 meters in diameter. The sedimentary formations in the northeast contain rocks deposited between 400 and 200 million years ago during the Devonian to Permian periods. Fault lines run northeast to southwest through Hong Kong, creating natural harbors including Victoria Harbour and Tolo Harbour.
Reclamation has added 70 square kilometers to Hong Kong's land area since 1842. Central District on Hong Kong Island extends 500 meters north of its original 1841 shoreline. Chek Lap Kok Airport occupies 12.48 square kilometers of reclaimed land north of Lantau Island, completed in 1998 by leveling two islands and filling seabed between them. The Kowloon Bay Business Area sits entirely on land reclaimed between 1958 and 1997. West Kowloon Cultural District covers 40 hectares of land reclaimed in the 1990s. Reclamation projects reduced Victoria Harbour's width from an average 2 kilometers in 1842 to 1.2 kilometers by 2000. The Protection of the Harbour Ordinance, enacted in 1997, restricts further reclamation within harbor boundaries.
The Tsing Ma Bridge connects Tsing Yi Island to Ma Wan Island with a main span measuring 1,377 meters, the seventh-longest suspension bridge span globally when completed in 1997. The bridge forms part of the transportation link to Chek Lap Kok Airport, carrying both road and rail traffic on two decks. The Hong Kong-Zhuhai-Macau Bridge, opened in October 2018, extends 55 kilometers from Hong Kong through the Pearl River Delta to Macau and Zhuhai. The main bridge structure measures 29.6 kilometers. A 6.7-kilometer underwater tunnel section passes beneath the Pearl River shipping channels at depths reaching 44 meters below sea level. The bridge connects to Hong Kong at an artificial island built northeast of Chek Lap Kok Airport.
Victoria Harbour handles container throughput that reached 17.8 million twenty-foot equivalent units in 2022. The harbor maintains 24 berths capable of handling vessels with drafts up to 15.5 meters. Kwai Tsing Container Terminals on the western Kowloon shore operate nine terminal facilities across 279 hectares. The natural typhoon shelter formed by the harbor's orientation has protected vessels since maritime trade began. Water depth in the main shipping channel averages 12 to 15 meters without dredging, a function of tectonic faulting that formed the harbor basin.
Kowloon Peninsula extends 10 kilometers north from Victoria Harbour to the mountain range formed by Lion Rock, Kowloon Peak, and Tate's Cairn. The peninsula's width varies from 5 kilometers at the harbor front to 2 kilometers at Boundary Street, originally the northern limit of British-controlled territory from 1860 to 1898. Stonecutters Island, formerly separate, became joined to the Kowloon mainland through reclamation completed in the 1970s. The island covers 0.68 square kilometers. Kowloon Bay indents the eastern shore of the peninsula, formed by natural coastline now entirely reclaimed for industrial and residential development.
The New Territories extend from the Kowloon mountain range to the Shenzhen River border with Guangdong Province. The 1898 Second Convention of Peking leased this area to Britain for 99 years, a period that determined Hong Kong's return to Chinese sovereignty in 1997. The Sai Kung Peninsula forms the eastern portion of the New Territories, characterized by volcanic rock coastlines and marine parks. Mirs Bay defines the northeastern boundary, opening to the South China Sea. Tolo Harbour, a sheltered inlet on the peninsula's western side, extends 12 kilometers inland. The northwestern New Territories contain the primary remaining agricultural areas, including the Yuen Long and Ping Shan plains where rice cultivation occurred until the 1970s.
Lantau Island doubles the size of Hong Kong Island but contains 3 percent of Hong Kong's population. Chek Lap Kok Airport occupies the island's northern shore. Ngong Ping plateau on Lantau's western peaks sits at 500 meters elevation. Po Lin Monastery, established on Ngong Ping in 1906, operates on 6.5 hectares. The Tian Tan Buddha statue at the monastery measures 34 meters tall and weighs 250 metric tons, completed in 1993 using 202 bronze pieces. Sunset Peak and Lantau Peak, at 869 and 934 meters respectively, dominate the island's topography. Tai O fishing village on Lantau's western shore preserves stilt houses built over tidal flats, a settlement pattern dating to the Ming Dynasty.
Lamma Island, 13.55 square kilometers, lies 3 kilometers southwest of Hong Kong Island. The island supports two main villages, Yung Shue Wan and Sok Kwu Wan, connected by a 5-kilometer footpath. Population numbers approximately 6,000. Cheung Chau, 2.46 square kilometers, sits 10 kilometers southwest of Hong Kong Island with a population near 23,000, the highest density among outlying islands. The island's dumbbell shape connects two granite hills with a narrow tombolo. Peng Chau covers 0.99 square kilometers between Lantau and Hong Kong Islands. Po Toi Island, 3.69 square kilometers, marks Hong Kong's southern extremity. Tap Mun, 1.69 square kilometers, lies at the eastern entrance to Tolo Harbour.
Hong Kong experiences a humid subtropical climate classified as Cwa under the Köppen system. The monsoon pattern creates distinct wet and dry seasons. Winter monsoons from the northeast bring dry continental air from November through March. Summer monsoons from the southwest carry moist maritime air from May through September. The annual average temperature measured at the Hong Kong Observatory headquarters in Tsim Sha Tsui equals 23.3 degrees Celsius based on the 1991-2020 climate normal period. January mean temperature measures 16.3 degrees Celsius. July mean temperature reaches 29.2 degrees Celsius. The highest temperature recorded was 36.6 degrees Celsius on August 22, 2017. The lowest temperature measured 0.0 degrees Celsius on January 18, 1893.