Berlin Tegel Airport is notable for its hexagonal main terminal building around an open square, which makes walking distances as short as from the aircraft to the terminal exit. The airport was scheduled to close in June 2012 after Berlin Brandenburg Airport (BER) opened, but due to ongoing delays with BER, the future of Tegel is uncertain. A campaign was launched to keep Tegel Airport open, which gathered signatures for a referendum for voters to decide on the future of the airport. While the referendum was non-binding, it did result in a majority of votes cast in favor of keeping Tegel open and
Airport city logically combined elements that reinforce each other. Services and facilities are designed to guide travelers easily through the airport process. Access is key for passengers, cargo, businesses, and residents, many of whom work in the airport city. "Time" has named it as one of "10 ideas that will change the world". The chapter "The Way Forward" from "Global Airport Cities" describes the basic airport city drivers, which have evolved with different spatial forms predicated on available land and ground transportation infrastructure: The most common airside and landside airport city commercial activities include: duty-free shops and airline lounges; restaurants, catering, and