Prince Philip at Incheon Airport Construction Site

The video discusses the future expansion of voting facilities, which will eventually include 153 voting gates. It highlights the Great Hall area, a large open space without internal support structures. Additionally, the terminal building will offer various amenities such as hotels, restaurants, business rooms, saunas, and other commercial establishments for travelers' convenience.

What is meant by 'internal support structure' in relation to the open space?

What types of establishments will the terminal building include for travelers' convenience?