CHICAGO (CBS)—The next step in a new and improved O’Hare Airport for the 21st century begins today.

The City of Chicago will break ground at 10:45 a.m. on a $1.2 billion expansion of Terminal 5, the international terminal.

When the project is completed, 10 new gates will open, along with more space for passengers to sit and new stores and restaurants.

(Credit: City of Chicago)

The terminal upgrade is expected to be finished by 2021.

The Terminal 5 project is the first in a series of projects ahead for O’Hare.

Five designs have been released showing a new global terminal, to replace the existing Terminal 2.

(Credit: City of Chicago)

It’s the centerpiece of an $8.5 billion expansion—the largest and most expensive in the history of the airport.

The new terminal will be funded with airline ticket fees, and is projected to open in 2028.

(Credit: City of Chicago)