When Pittsburgh International Airport opened its last great modernization project in 1992, it was hailed as the airport of the future. The then-novel configuration divided the airport into two main structures — a landside terminal for check-ins, security screening, and baggage claims and an airside concourse with an X-shaped footprint that was in the middle of the landing field, where passengers would catch their planes. The two were joined by an underground automated people mover.

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