In which city lies the headquarter of NATO?

Explanation

NATO (North Atlantic Treaty Organisation)is an international organisation for political and military defense cooperation in the North Atlantic. The cooperation was first established in 1949 and back then consisted of 12 member states. Since then, the Organisation has been enlarged in several rounds. One of these was in 2004, when a range of the former Warsaw Pact countries were admitted. The Dane Anders Fogh Rasmussen took over the post as NATO Secretary General on 1 August 2009. NATO is headquartered in Brussels.