Translation of plummet in German

We decided to fly directly to Hanoi and booked a flight for the same day. Before we left we still had some time to visit the War Remnants Museum. One could see the former headquarters of the South.
Try to speak and think in English every time. I have just returned from Europe where I spent a month on holiday. My wife Susan and I went to Barcelona, Madrid and Paris, where we saw lots of beautiful things.
A little information about me: I am 33 years old and my wife Anna and I have 3 children. We live near Dortmund. I work as a train driver in the Deutsche Bundesbahn. Do you know Germany?