President Donald Trump recently unveiled a $22 billion plan to rebuild Washington Dulles airport.

The plan calls for replacing concourses and adding a large parking garage. The landmark ‌main terminal designed by Finnish architect Eero Saarinen will be preserved. That distinctive structure features a sloping roof that sweeps up toward the sky on opposite sides.

About 5 million sf of airport space will be renovated or built new. United Airlines will get a new 435,000 sf, 14-gate concourse.

The plan is one of the largest U.S. airport overhauls ever proposed and will be funded via municipal bonds. United is the largest airline at Dulles, handling about 70% of the facility’s traffic.