HKG -- Hong Kong International Airport is a hub airport for the rest of China and Southeast Asia, 40km west of Hong Kong, with a train link to the city centre.
Level 8 Mezzanine is not restricted and has a great view of the departures hall.
Level 7 (check-in) offers a variety of eateries: Banana Leaf Asian Food Square, Coffee Club Xpress, the Fook Ming Tong Tea Cabin, and the Wing Wah Cake Shop. Bank of China, Hang Seng Bank, and Hong Kong Bank ATMs are in the check-in hall.
Level 6 (boarding level) has a variety of eating outlets, including Chinese and international cuisines, Stop and Eat in the North Concourse, and Cyberbreak Internet Café, along with shop-til-you-drop syndrome. There are Bank of China ATMs in the east hall. Bank of East Asia ATMs are in the west hall. Bank of America (Asia) ATMs are also in the east hall.
Level 5 (arrivals) has no food or drink outlets -- a missed market here. There are Bank of East Asia ATMs and the meters-and-greeters hall.
Ground transportation includes dedicated express railway, limousines, taxis, buses, and long-distance coaches. Local ferry goes to Chek Lap Kok and Tuen Mun, an area in the New Territories north of the airport, from 6am to 11pm, via bus at passenger terminal to pier.
I remember seeing military personnel with automatic machine guns at the airport on one occasion at the old airport.