Germanwings GmbH is a German low-cost airline based in Cologne and a wholly owned subsidiary of Lufthansa. Its main hubs are Cologne Bonn Airport, Stuttgart Airport, Hamburg Airport, Berlin Tegel Airport and Düsseldorf Airport; further bases are Hannover Airport and Dortmund Airport. It operated independently until October 2015, when a merger with its sister company Eurowings was started which will be completed during 2016.