Hofburg, the Imperial Palace of Vienna
I went to this place after I bought the ticket of Lange Nacht der Museen. This place is quite near with the church I usually attended, but never passed this place.
The Hofburg is the former principal imperial palace of the Habsburg dynasty rulers and today serves as the official residence and workplace of the President of Austria. It is located in the center of Vienna and was built in the 13th century and expanded several times afterwards. It also served as the imperial winter residence, as Schönbrunn Palace was the summer residence.
Numerous architects have executed work at the Hofburg as it expanded, notably the Italian architect-engineer Filiberto Luchese, Lodovico Burnacini and Martino and Domenico Carlone, the Baroque architects Lukas von Hildebrandt and Joseph Emanuel Fischer von Erlach, Johann Fischer von Erlach, and the architects of the Neue Burg built between 1881 and 1913. (Source: Wikipedia)