Berliners voted to keep the historic Tegel airport open even after a new international hub is completed, creating a headache for the German capital's government, which wanted it closed.
Tegel sprang up in just 90 days in 1948 to support the Berlin Airlift, a huge operation to ship supplies and thwart a Cold War Soviet blockade. It is much-loved by many Berliners and business travellers for its proximity to the city center.
Berlin's government will now have to rethink its plans to close Tegel after some 56 percent of voters supported the non-binding referendum on Sunday, the same day as Germany's federal election, to reconsider the proposal.
This had envisaged the closing of Tegel six months after the Berlin Brandenburg International (BER) airport - a grand project bedeviled by repeated construction and planning problems - finally starts operating. It still has no fixed opening date.
Michael Mueller, Berlin's mayor said the result created a "very, difficult situation" and told rbb radio he would now talk to the airport's state owners about taking a different approach that could be "legally and financially challenging."