Tegel the end of 1948. Tegel is chiefly known for being the location of Berlin-Tegel "Otto Lilienthal", Berlin's main airport. It also houses the Tegel Penitentiary, Germany's largest prison with about 1,700 inmates as of 2007, known from Alfred Döblin's 1929 novel Berlin Alexanderplatz. One of Berlin's largest shopping malls "Borsighallen" is located in the former locomotive manufacturing halls of the "Borsigwerke". There is also the "Villa Borsig" at the shore of Lake Tegel, the former residence of the Borsig family. Today it is a school for future diplomats. Beside this Tegel is an extensive residential district with some industry. With
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