Hofburg Imperial Palace (Vienna)

 castle, museum, UNESCO World Heritage Site

The Hofburg is the former principal imperial palace of the Habsburg dynasty. Located in the center of Vienna, it 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. Since 1946 it is the official residence and workplace of the President of Austria.
Since 1279 the Hofburg area has been the documented seat of government. The Hofburg has been expanded over the centuries to include various residences (with the Amalienburg and the Albertina), the imperial chapel (Hofkapelle or Burgkapelle), the imperial library (Hofbibliothek), the treasury (Schatzkammer), the Burgtheater, the Spanish Riding School (Hofreitschule), the imperial mews (Stallburg and Hofstallungen).
The palace faces the Heldenplatz (Heroes Square) ordered under the reign of Emperor Franz Joseph I, as part of what was planned to become the Kaiserforum [de] but which was never completed.
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.