We loved our stay in the Operngasse. Jessica met us on arrival and explained everything about the apartment. It was clean, comfortable and well-equipped for our stay. Even though it's on a main street, it's really quiet, The Freihausviertel is a brilliant area to stay: plenty of good shops, cafes and restaurants in the area, but a short walk to the metro and trams at Karlsplatz and the main sights of Vienna. I would definitely recommend the apartment to anyone visiting Vienna, and we would definitely book again.