Markus Rach: I recommend the tour through the opera - goes for about 45 minutes - thus doable. It's quite interesting to see the backstage area which is three times as large as the opera guest area...
Magnus Wurzer: If you take the time to walk uphill through the park, past Neptune fountain, to the "Gloriette" building - you will have a wonderful view over the city. Which gets even better when you climb onto the