Vienna's Imperial Palace is one of the biggest palace complexes in the world. The oldest parts date to the 13th century, with construction having continued right into the 20th century. The Imperial Palace was the residence and seat of government of the Habsburg emperors until 1918. Today, it is home to numerous museums with outstanding collections, the Spanish Riding School, a congress center, the seat of the Austrian Federal President as well as the historic Heldenplatz. https://www.wien.info/en/sightseeing/sights/imperial/hofburg-vienna

The former summer residence of the Habsburgs impresses with imperial ceremonial rooms and magnificent gardens. Maria Theresa, Emperor Franz Joseph, Empress Elisabeth and others once resided here. Schönbrunn Palace is one of Europe's most beautiful Baroque complexes and has been in the possession of the Habsburgs since 1569. The wife of Emperor Ferdinand II, Eleonore von Gonzaga, had a pleasure palace built on the site in 1642 and called the property "Schönbrunn" for the first time. The palace and garden complex created from 1696 onwards following the siege of Vienna was complete redesigned under Maria Theresa after 1743. Today, due to its historical significance, its unique layout and magnificent furnishings, the palace is a UNESCO World Heritage site. https://www.wien.info/en/sightseeing/sights/imperial/schoenbrunn-palace