There are three main places to visit in Vienna that each is a symbol of the city in its own right. The first is Ringstrasse, a circular avenue around the center of Vienna separating the neighborhoods of Hofburg and Stephansdom from the rest of the city. This avenue is home to many of the most important things to see in Vienna such as the Hofburg Palace, City Hall, the Stock Exchange, the Burgtheater, the Votive Church, the University, the Museum of Art History, the Museum of Natural History and the Parliament. The Parliament is a huge neoclassical building with two large chambers joined by a large central portico with impressive views of the interior.
A visit to the State Opera is the second on the list of important things to do in Vienna. It's the most important opera company in the country and is famous throughout the world. You can visit the lobby, the 2,800 seat auditorium, the stage, the salon in which Francisco Joseph rested during intermissions, or the marble chamber.
Some of the most important attractions in Vienna are its palaces: Schönbrunn Palace, Hofburg Palace and the Belvedere Palace. The latter is a set of two palaces, the Upper and Lower Belvedere, where the works of artists who shaped the city during the Golden Age of Vienna are housed. Some of the most important rooms are the Hall of Grotesques, the Marble Gallery and the Hall of Mirrors.
Out of all the stuff to do in Vienna, save time to visit the Danube Tower, a 252 meter tall structure from which you can see most of the city, the popular Prater theme park, and the peculiar Hundertwasserhau building. If you're still curious about what to do in Vienna have a look at the recommendations from the minube community and find the all the best Vienna activities and Vienna attractions.