The observation deck inside the restricted area of HK airport
When you’re leaving Hong Kong you may be busy with the check-ins, customs and immigrations, eating and shopping at the airport, but don’t forget to save some time for some sightseeing too, to enjoy the scene of the runway and the HKZM bridge.
If your gate is in the midfield, which means gate 201-230, you can visit the observation deck next to gate 219 which is at one end of midfield.
It is indeed a smoking area but named as observation deck. The view is awesome where you can see airplanes going around and also take-offs.
If you look at the far end, you can see HKZM bridge when connects Hong Kong and Zhuhai and Macao.
There are also another observation decks such as two in the middle of Midfield Concourse, which are also smoking areas, people can see another side of the airport with planes at different bays over there.
Transportation: Take Automated People Mover to gate 201-230
Address: Midfield Concourse, Hong Kong International Airport