Berlin Brandenburg Airport surrounding the three existing airports — Tegel, Schönefeld and Tempelhof. Therefore, it was mandatory for Tegel and Schönefeld to close (Tempelhof was already decommissioned in 2008) once Berlin's air traffic is concentrated at the new airport. By 2009 the construction cost was budgeted at €2.83 billion. FBB raised the financing for the project by a credit raising of €2.4 billion, a bank deposit of €430 million by the FBB partners and an additional €440 million of equity capital provided by FBB. During construction, it became clear that the airport would become significantly more expensive due to underestimating the actual costs,
Airport city Airport city Airport city is the "inside the fence" airport area including the airport (terminals, apron, and runways) and on-airport businesses such as air cargo, logistics, offices, retail, and hotels. The airport city is at the core of the aerotropolis, a new urban form evolving around many major airports. The airport city model recognises that an airport can do more than perform its traditional aeronautical services, evolving new non-aeronautical commercial facilities, services and revenue streams. Airports are now routinely targeting non-aeronautical revenue streams amounting to 40–60% of their total revenues. Industry leaders and researchers share best practices on non-aeronautical revenues