Incheon Airport officially opens its second terminal Thursday, marking its first large-scale expansion in 17 years armed with smart technologies. 

Passengers at Terminal 2 will be able to complete the whole check-in process in 30 minutes via a host of smart technologies, such as automated check-in services and a face-recognition system, according to Incheon Airport. In addition, larger waiting areas in the departure and arrival halls will ease overcrowding. 

There are 62 self-check-in machines at the new terminal, which translates to 3.44 units per 1 million visitors. At Terminal 1, there are 92 units, but it only translates to 1.7 units per 1 million visitors due to the large number of travelers. 

With the opening of Terminal 2, the airport expects to handle 72 million passengers and 5 million tons of cargo annually.

South Korea’s largest flag carrier Korean Air and three foreign carriers -- Delta Air, Air France and KLM Royal Dutch Airlines -- will serve passengers at Terminal 2. All four airlines belong to the SkyTeam airline alliance. Asiana Airlines and 85 other airlines will remain in Terminal 1. 

Terminal 1 and 2 are located on opposite sides of the airport and separated by runways. Buses and trains from Seoul and the suburbs stop at both terminals. 

Officials estimate that around 800 passengers may go to the wrong terminals during the first week of the grand opening. Similar incidents happened last week, when some 160 travelers went to Terminal 2 to check-in, without realizing the new terminal had not yet opened, or got off at the wrong stop. 

Airport officials said they would run underground shuttle trains connecting the terminal buildings, but these will only be available for transfer passengers. 

By Kim Da-sol (ddd@heraldcorp.com)