Kai Tak Airport, which had served Hong Kong since 1925, was operating in conditions that would have been farcical if they weren't so consequential. A single runway extended into Kowloon Bay from the heart of a densely populated urban area. Approaching aircraft threaded between apartment blocks, their flight paths so low over the city that residents could reportedly read cockpit instruments from rooftops. Noise pollution exceeded 105 decibels in Kowloon City, affecting an estimated 340,000 people. By the early 1990s, one in three flights experienced delays. The airport was handling more passengers and cargo than it had ever been designed to hold. A 1974 planning study had already identified Chek Lap Kok as the logical replacement. A full decade passed before the project advanced, and even then, political tensions between the British colonial government and Beijing slowed financing and nearly stalled construction entirely.

The politics surrounding the airport's construction were as complicated as the engineering. When the British colonial government announced the project, Beijing objected — worried, among other things, that a departing colonial power was committing Hong Kong's finances to a massive project without consultation. Financial institutions paused lending. Construction halted in places. Agreements were eventually reached, but the clock was running. The original plan had been to open before the handover in July 1997; instead the airport opened a year after, on 6 July 1998. Jiang Zemin, President of China, officiated at the opening ceremony. Hours later, Air Force One carrying Bill Clinton became the first foreign visitor to land. Then the flight information display system crashed. The cargo communications link went down. Someone accidentally deleted a critical cargo database. For days, the airport could not process air freight automatically. The old Kai Tak cargo terminal had to be temporarily reopened to handle the overflow. It was, by any measure, a chaotic beginning.

The chaos did not last. Terminal 1, with a floor area of 570,000 square metres, was the largest passenger terminal building in the world when it opened — a distinction it has since ceded to Dubai and Beijing but still holds in the top tier. Foster and Partners designed the roof; Ove Arup handled structural engineering. The glass sides were engineered to fracture under typhoon-force wind pressure, releasing stress and allowing the building to survive storms that would destroy a more rigid structure. The airport runs 24 hours a day and handles more than 100 airlines flying to over 180 cities. In 2024, it processed 53.1 million international passengers, ranking it 29th globally by that measure. Since 2010, it has been the world's busiest cargo airport by traffic — the SuperTerminal 1 facility alone, at 328,000 square metres, is the world's second-largest standalone air cargo handling facility.

For most of its life, VHHH operated with two parallel runways, each 3,800 metres long and 60 metres wide. The south runway handles takeoffs and cargo; the centre runway is rated to Category IIIA precision approach, allowing landings in as little as 200 metres of visibility. Together they moved over 60 aircraft per hour at peak capacity. The airport reached that ceiling faster than planners expected. In 2012 the Hong Kong government approved an HK$141.5-billion expansion: a third runway built on 650 additional hectares of reclaimed land to the north, roughly the size of Gibraltar. The North Runway opened in July 2022. Terminal 2 is undergoing major expansion and was expected to reopen in 2025. The airport's updated Master Plan projects handling up to 620,000 flight movements annually — one departure or arrival every 36 seconds around the clock.

Hong Kong International Airport's role extends well beyond Hong Kong. It sits at the apex of the Pearl River Delta, one of the world's most densely industrialised manufacturing regions, and has built extensive connections to serve the movement of goods and people across the whole zone. The SkyPier high-speed ferry terminal, opened in 2003 and expanded in 2009, allows passengers arriving by air to connect directly to ports in Macau, Shenzhen, Dongguan, Zhongshan, and Zhuhai without clearing Hong Kong customs and immigration. Cross-border coaches operate from the airport to 90 cities and towns in the Pearl River Delta. The airport employed approximately 60,000 people at the start of 2024, and in 2018 its air travel industry contributed US$33 billion — roughly 10.2% of Hong Kong's GDP — to the territory's economy. The mountain that used to stand here has been doing considerable work.