Visiting Vienna is a different experience for different people, and there are many sights to see. Most people will head for the Schonbrunn Palace to see the collections of art and the formal gardens, but the nearby Belvedere is also well worth seeing, and has an excellent collection of paintings and sculptures by most major artists.
The Hofburg is also high on the list of attractions. The palace, which occupies a vast space in the Innere Stadt, was completed over many centuries by the ruling Hapsburg family, and is the current home to the Vienna Boy's choir who perform there every Sunday throughout the year and the Spanish Riding School.
The Natural History Museum and the National museum (Kunsthistorisches Museum) face each other across the Maria Theresien Platz, and their respective collections are the equal of any in Europe.
The renaissance style Staatoper (The Opera House) was completed in 1869 and is for many one of the most important buildings in this musically obsessed city. It receives vast state subsidies to attract audiences, and relatively cheap tickets for most performances are sold daily on a first come first served basis. Unless you pre-book, you need to rise early in the morning to queue up and guarantee yourself a seat.
